Disclosure: We sometimes use affiliate links which means we may earn a commission if you buy something through our links.

A few weeks ago I was helping a client choose a transactional email system to enable them to send invoices, receipts, reminders, and notifications to their users. As the decision was quite time consuming and required many hours of research, I thought it may be helpful to write up some of my findings so that others didn’t have to spend quite so long getting their head around the different options.

What is a Transactional Email?

A transactional email is an automated system that sends a receipt, invoice, or confirmation when a user completes a certain action. For instance, after purchasing a product and having a confirmation and receipt sent to their email address. Or a password reset link sent when the user requests.

These differ from marketing emails which are aimed at generating leads and conversions.

First things first, there’s no ‘one sizes fits all’ option

It quickly became clear that there was no obvious winner – all of the transactional email services will do virtually everything that you’ll realistically need, so making an informed choice is about understanding which services do what you need the most better than the others, and of course, there’s the cost.

So, let’s start off by looking at each of their strengths and weaknesses, then we’ll compare the costs, and look at some of the important considerations when choosing an email system.

The pro’s and con’s of transactional email service providers

Out of the fifteen or so popular transactional email services that exist, there are only a few that really bring something unique to the table; Sendinblue, SendGrid, Amazon SES, Mandrill, Mailgun, Mailjet, and Postmark. Most of the other services either lack a compelling value proposition or are just slightly worse / more expensive copycat versions of one of the above.

Sendinblue – 5/5

Sendinblue enable you to send up to 9,000 emails/month free of charge (for as long as you like), making it a good platform for startups to start on.

Their pricing remains one of the most cost-effective options as you scale up (unlike services like SendGrid which start off quite affordable but become quite expensive as you scale).

Their user interface is very clean, and in addition to transactional email you can also use Sendinblue for normal email marketing campaigns, marketing automation, and transactional SMS messages.

While they don’t have the strong brand/reputation of SendGrid or Mandrill, they seem to tick a lot of the boxes when it comes to deliverability, good reporting, fair pricing, and a good overall product.

Their API and documentation are very extensive, and they also have a good variety of integrations and webhooks for getting your app/service connected.

You can learn more about Sendinblue here.

Amazon SES (Simple Email Service) – 3/5

When competing on price, it’s hard to beat Amazon. At $0.10 per thousand emails, Amazon SES is extremely cost effective and scalable. However, the AmazonSES interface is messy to say the least, and playing around with their API can be a real headache. There are a few workarounds that will enable you to get the low cost of Amazon SES without the poor interface. One way is to use a tool like Sendy, which is a self-hosted interface that uses the Amazon SES API to send your emails.


Whether or not this is the best option depends on your budget, coding ability, and patience. While it’s the cheapest option by far, Amazon fall short on their service, features, and support. You can’t use dedicated IP addresses, you are only able to send emails from verified addresses, and the analytics are extremely limited. Consider Amazon SES the bare bones option – if all you need is to get emails into inboxes, and nothing else, this is probably the best way to go.

SendGrid – 3.5/5

SendGrid are arguably the industry leaders in the transactional email space. While SendGrid are neither the cheapest nor the most expensive option, what’s attractive about their offering is their incredible email analytics, 24/7 live support, easy integration with a dead simple API, and their reputation for having good deliverability rates.

Sendgrid Analytics

While other options performed better in certain areas, SendGrid have a good overall balance of important features. The only reason I’ve not scored them higher is based on price and quite a lot of negative comments from users left below:

I have been using SendGrid for the last few years as a paid platinum account user. Whilst initially great, the quality of their service has decreased to a level where they are constantly embarrassing me in from of our clients. – James, data-group.com.au

Having used Sendgrid for 3 years until stopping recently, my experience has been that they’ve gotten so many large corporate clients that they neglect smaller customers. I’m guessing that small customers get thrown on one PowerMTA which is not managed well, if at all, while big corporations get “white glove” service. – Frank, coldcallinginsider.com

Mailjet – 2/5

My first impressions of Mailjet weren’t great – they responded to an email I sent them with a link to contact them on their website support forum. For a company specialising in email, this strikes me as a bit incompetent. While Mailjet prides themselves on their sophisticated support system, I much prefer SendGrid’s quick and reliable 24/7 approach to MailJet’s ticketing system.

Mailjet statistics

However, with that aside, their interface is really nice and their mobile apps are a nice tough. Generally though, at roughly the same price as SendGrid it’s tough to see why you’d choose Mailjet over them. If anyone’s had any experience with Mailjet it’d be great to hear about it in the comments below.

Mailgun – 2/5

My research into Mailgun was generally quite underwhelming. Their analytics are extremely basic, the setup process is quite overwhelming, and while their pricing is nice and simple, it’s neither competitive nor overly expensive. On top of that, they took ages to respond to support queries.

It seems that the main benefit with Mailgun is their developer focus. Everything about their service is designed with developers in mind, and it appears that their strength is in the technicalities, and getting the developers on board.

Mandrill – 0/5

Prior to March 2016, Mandrill were a very viable option for transactional email (we previously scored them as 3/5). Owned by Mailchimp, the team built a great-looking product. While the analytics were quite basic, their dashboard and interface was fantastic and made the whole set up process really simple.

Mandrill lost its edge when they decided to make it an add-on for Mailchimp users. Now, if you want to use Mandrill for transactional email you have to sign-up for Mailchimp, which makes the cost of sending transactional email through Mandrill significantly more expensive.

While I could elaborate on the different aspects of Mandrill’s service, the general consensus from the development and startup community is that Mandrill is no longer a viable option for transactional email. As such, we’ll swiftly move on…

Postmark – 4/5

Postmark has one of the best developer experiences of the tools listed.

Having recently moved TrueNorth (our latest venture) onto Postmark, our engineers mentioned that it was significantly easier to build custom templates and work with their API than any other services they’ve used. Unexpectedly, our conversion rate also increase when moving to Postmark as a result of the ultra-fast deliverability improving the percentage of people signing up with our magic sign-in links.

It should be pointed out that Postmark isn’t the cheapest tool. You also won’t find many bells and whistles on their platform for marketing teams or non-email features. If, however, you just need a reliable email server that does transactional email well, Postmark are a great option.

Finally, Postmark have provided us with a “friends and family discount”. If you do choose to use them this will get you (and us) a free month of usage when you ping their support team.

Comparing the price of different transactional email services

Due to the sliding scale pricing structure of most transactional email services, I’ve compared the prices for sending a different quantity of emails. This is important because some of the providers are more cost effective for low volumes, where others are more cost-effective at high volumes.

Cost at 40,000 emails per month:
AmazonSES – $4 / month
Sendinblue – $7.37 / month
SendGrid – $9.95 / month
Mailgun – $15 / month
MailJet – $17.49 / month
Postmark – $30 / month

Cost to send 250,000 emails per month:
AmazonSES – $25 / month
Mailgun – $120 / month
Sendinblue – $137 / month
MailJet – $178.95 / month
SendGrid – $199.95 / month
Postmark – $250 / month

Cost to send 1,000,000 emails per month:
AmazonSES – $100 / month
Mailgun – $421.50 / month
Sendinblue – $445 / month (+ free dedicated IP)
MailJet – $499.95 / month
SendGrid – $534.95 / month
PostMark – $750 / month


As mentioned, there’s no ‘one sizes fits all’ option when it comes to choosing a transactional email service – it simply depends on what’s most important to you, and how much you’re willing to spend.

Generally, I’d say the Amazon SES is the best option for those looking for a cost effective and ‘no frills’ solution. For anything more sophisticated it’s most likely going to be a toss up between Sendinblue and SendGrid.

I’d love to hear about anyone’s experiences with different transactional email services in the comments below – both good and bad. If you work for one of the services, please add a disclaimer in your comment so that others are aware.

Hit your growth goals

TrueNorth is the Growth Marketing Platform to focus, align, and track marketing in one place, with everything and everyone working towards your goal

Visit TrueNorth.io

Marcus Taylor

Marcus Taylor

Marcus Taylor is the founder of Venture Harbour. He’s also an early-stage investor, advisor & the youngest Patron of The Prince's Trust.

More from Marcus
  • Follow Marcus


  • Jens-Christain Finnerup says:

    Postmark has a 10k emails/month pricing tier at only $10 which makes it neatly comparable to the other services to get started. Its still 4x the price per volume as say Sendgrid, but since i didnt need the extra 30k emails that sendgrid provides at the same price, the two became comparable in pricing.

  • Keith says:

    STAY AWAY FROM MANDRILL. It’s not a reliable service. Too much downtime and randomly failing emails. My company started using them 2 years ago but over the past 6 months the service has gone to hell. We are moving to a new platform.

  • Sebastian Melgin says:

    Hi. I want to say that we’ve using SendGrid and is a very good service … but with a very bad support services … We are having issues trying to send emails with attachments and since last week, the support people in SendGrid seems to take that issue as something with a lack of importance, just because they respond the ticket once a day or maybe once in 3 days … Good producti with bad service … is not a good formula for success …

  • Evan says:

    Looks like SendInBlue’s free plan limits you to 300 now.

  • laurynn says:

    I wanted to echo the sentiments on Sendgrid. We started using them in Jan ’18. From Jan until April, our blocked rate was under 5%. In May, 14.56% of our emails were blocked, most because of IP throttling. Yes, Sendgrid has 24/7 support, but their answer to this spike in blocks is that we need to change our plan from $9.99/month to $79/month.
    The frustration, perhaps obviously, is that I was not given this choice until months after deciding to go with Sendgrid. I chose the plan based on how many emails we send. If I had been advised at the beginning (or at least the first few months) that the real cost of sending emails was much higher, I would have made a different choice.

  • Fab says:

    Hello, any information about the Hotmail “421 RP-001” blocking message ? It looks like they are now blocking a lot of shared IP like the one used by freemium emails services (i saw some many recent complaints from Spark users but also MailGun)

    For instance on my Sparkpost account many emails to Hotmail emails are not sent..

    That’s a real problem and i wonder if this happen on all “freemium” email services ?

  • Daniel Lewis says:

    I whittled it down to these five as the most viable solutions

    AmazonSES – Cheapest at high volumes (but see Authmailer too)
    SendinBlue – Going on other comments here this was the original solution given that has no negative reviews – Reasonably priced too
    Authmailer – Very similar pricing to AmazonSES
    ElasticEmail – cheap at lower volumes (e.g. under 100k) – first 40k emails are free – but have they been around long?
    SparkPost – the cheapest – first 100k emails are free – but have they been around long?

    • Steve Tuck says:

      Hi Daniel,
      Disclosure: I work for SparkPost.
      While the name is new, we’ve worked in email (as Message Systems and Port 25 / PowerMTA) since 1999. We are known for supplying the sending engines behind 7/10 top ESPs, and some of the companies reviewed here. Across all of our solutions we deliver nearly 30% of the world’s legitimate (non-spam) email, over 3 trillion messages per year.
      Two years ago we launched our own cloud SaaS offering, and it’s going really well. SendGrid’s former largest customers, including Pinterest and Zillow are now on our platform, and we have 20,000+ active customers overall. Some significant UK businesses also send through us.

  • Daniel Lewis says:

    I AM INDEPENDENT and just researching which one to use – I’ve read every comment so far and given a score of +1 for a good comment and -1 for a bad comment. The scores are …

    SendinBlue +6 -0 = 6
    AmazonSES +1 -1 = 0
    Postmark = +0 -0 = 0
    MailGun +0 -3 = -3
    MailJet +0 -6 = -6
    SendGrid +4 -11 = -7
    Mandrill = +6 -19 = -13

    Other services (some many not be ESPs) …

    customer.io (via segment.com)
    Message Bus
    Get Vero

  • Edward says:

    I’ve been using Mandrill for several years and have really enjoyed their service offerings, especially the web hooks and the inbound feature. However, now that it’s a requirement to have a MailChimp account to use Mandrill I’m looking to switch to another provider. I’m leaning towards Amazon SES.

  • Shin says:

    I had been using Mandrill over the last 2 years and I had no issue. However, since they became a plug in for MailChimp, I had been experiencing random delivery failures. No api log error or sending errors. I didn’t have a way to trouble shoot and I’ve made a move to Sendinblue. I hope it will work for me.

  • Eric B says:

    I’m here looking for a new transaction email service because our SendGrid experience has been quite poor. We were switching from Mandrill because of their strange and frustrating changes this year. Now on SendGrid, we are having some deliverability issues and customer support is really just dismal. I thought they’d be safe because of there brand recognition and large market share. I guess not!

  • Ryan Chew says:

    Sendgrid sounds great, provided they even let you use their service. I signed up, provided the details they asked for, and an email came in saying “Sorry, based on our checks we will not be activating your account. We wish you all the best in your future endeavours.”

    I wrote back to their support team saying “Hi, I’m trying to set up a new SAAS startup and I’d really like to use your service. I understand that I haven’t passed your checks, so please let me know what I need to do to verify I am who I am and get started.

    A support ticket came back with a canned reply:

    Hi there,

    Thanks for reaching out to SendGrid. Our provisioning team leverages a variety of data points such as IP reputation, input from the community, geo location, etc. Unfortunately based on the information you provided we will not be activating your account.

    I sincerely apologize for any inconvenience this may cause and wish you the best.

    SendGrid Support

    Nothing. No right of appeal. No “here’s the hoops you have to jump through to get started”. Just a straight flat out No.

    So I signed up for Sendinblue. Half an hour later I was sending emails through their api and I’ve been a loyal customer ever since.

  • Patrick says:

    As a heads up, at least with the free account, SendInBlue adds a tracking image to the email, and converts text mail into mime. There does not appear to be a way to turn that off. There’s also an hourly, daily, and monthly cap. Does have an easy setup process, though, and is free.

    Mailgun’s free account just has a monthly cap, but is much harder to set up. The dns setup requirement broke my host’s dns tool.

    great article

  • DC says:

    I was doing a research (after being dumped by Mandrill) and first signed up for a SendGrid account. WHAT A MISTAKE!

    I then tried to set up transactional emails with SendGrid on my server via their PHP script… tried the whole day yesterday to install and run their PHP library… and totally gave up. It was such a ridiculous process… Ended up with a big headache and eventually quit. They want you to upload 1.7 MB of PHP code just to send a single text-based transactional email! I contacted their tech support… nothing. Posted a ticket… nothing. I’m still waiting….

    So then I decided to do a Google search and found this site. And I am very glad that I did!!!! I tried SendingBlue account and it was amazing! Amazingly easy to set up my PHP script. Instead of 1.7 MB of PHP libraries, I needed to install just one PHP file that did all the work. Just one include. I tried their sample, and it was done. In about 10 minutes I could send transactional emails without any bounces or anything. Then next 10 minutes to set up webhooks. Done! Just that easy!

    It was also amazing that so far all my test emails reached accounts at hotmail, outlook, gmail — and all of them put them into Inbox. I remember it took a lot of finagling to make it work like that with Mandrill. And all that with a free account at SendingBlue. So far, I’m really impressed. So tomorrow I’m setting up SPF, DKIM and DMARC signatures. I need to contact them via email for that. But I am really optimistic.

    The bottom line, I AM NOT LOOKING back to SendGrid or Mandrill. Awful service! Do not fall for their promises of prompt tech support. THEY SUCK!!!!

  • usha says:

    Great review.We are looking at sending >1000 mails per hour and it should not get queued up for long. Which framework is best in providing efficient parallel threads?

  • John says:

    Mandrill now will cost a minimum of $30/month since they are requiring a paid subscription to MailChimp. This seems excessive and I will no longer recommend Mandrill.

  • james says:

    Mandrill does not scale well so be very wary. It works fine on small batches in the 10s but anything larger you get “Error too much mail” and it queues the email for sometimes hours.

  • So I’m still trying to understand Mandrill’s new pricing. If I want to send out 40,000 emails per month, I’d need to pay Mandrill $40 (according to their website) plus $10 to Mailchimp at a minimum. Does Mailchimp consider the people who I send transactional emails to as subscribers as long as they’re entered into the system?

    Cost at 40,000 emails per month:
    AmazonSES – $4 / month
    SendinBlue – $7.37 / month
    SendGrid – $9.95 / month
    Mailgun – $15 / month
    MailJet – $17.49 / month
    Postmark – $30 / month
    Mandrill – $40/month + Mailchimp monthly plan ($10+)

  • I had a bad experience with SendGrid, 3 separate problems (import failure, login credentials problem, cancellation page unreliable).

    I’ve since switched to ElasticEmail after tons of research on the others you mention. They are a diamond in the rough.

  • Well, now that Mandrill decided to do away with themselves and go to mailchimp *YUCK* I’ve been forced to move myself and like a dozen clients over to something else. Your write up is very good, and I love the options – Amazon SES is so ugly, and so archaic for being an industry leader in damn near everything. Going to give it a shot – thanks for all your help! – J Hunter Virtual Assistant

  • Dan Levin says:

    It’s interesting what you wrote about SendGrid. My company dropped that ESP after a couple of years. We just grew tired of their turning every technical support inquiry or issue into a sales pitch, such as, “If you would just buy this product from us then your problem would be solved.” I finally decided to find a company that treats its problems like its own and the customer doesn’t pay the cost of fixing them. Like you wrote, SendGrid does not really care about small business customers. I’d advise other smaller businesses to avoid that service and costs which will surely escalate.

    P.S. If anyone has doubts about what I’m saying, just respond and I’ll post a long email chain with SendGrid that will make you laugh and cry. It’s the like famous clip of someone trying to cancel an AOL account and, no matter what, cannot get it done. SendGrid just wouldn’t recognize that its assigned IP was on too many blacklists.

    • Dan

      Great post

      Sendgrid do not warn potential customers that if one signs up to use a shared IP cluster, you may be subject to spam blacklists. Since deliverability is the reason I signed up in the first place, Sendgrid have let my business down very badly. They, as you say in your post above, ignore your requests to change to different shared IP cluster [requested because of the spam blacklists], but instead just keep sending you emails saying that is beyond their control and that I need to sign up to a dedicated, and more expensive IP address.

  • Bill says:

    We’ve been using mandrillapp as an SMTP server for our regular email (through Outlook, Thunderbird and Android/IOS mail clients) just for deliverability. Their changes in policy have forced us to look elsewhere.

    I’m currently trying SES, but I’m concerned about complaints that they’re being blocked by the big anti-spam guns. How do the other SMTP servers line up in the deliverability arena? My wife uses email to connect with clients and co-workers and cannot afford to have anything marked as spam.

  • Ajay says:


    I came to know sendgrid has lite plan which is of the same cost as that of amazonses..per 1000 emails 0.10$ even amazon ses charges the same…So shouldnt we go with sendgrid with the king od features and ease they provide?

  • Helen F says:

    Mandrill have now dropped all support for their free tier, with very short notice. They originally agreed to let those who were already onboard keep the service, but that has now been revoked. Their cheapest offering is $360 per year. I’m pretty annoyed as I’d just set everything up with them. Disappointing, but now know not to trust them (and even mail chimp) in the future.

    Going with mailgun, as it will work for my needs afaik

  • Adrian Gray says:

    Hi All,

    Thanks for the informative post and discussion below it, was wondering if anyone had used Get Vero? As curently looking for a new vendor and this one is coming up but have never heard of them.


  • Maik says:

    Since feb 24, Mandrill has dropped their free 12K messages plan. You’re now forced to create a paid Mailchimp account ($9.99/mo) and the smallest plan is 25K messages/mo for $20, minimum. So, for any small outfit that sends less than 12K messages per month, that’s from $0 to $360 per year.

  • Tevya says:

    You may want to update the Mandrill part. They just announced some major changes. You now have to have a paid MailChimp account, then can add Mandrill on top of it. They’ve taken away all the free accounts/tier for Mandrill. You’re also not allowed to send marketing type email with it any longer per the ToS. Transactional email only. So basically overnight they went from a really great option for lots of us, to no option at all.

    If you already pay for MailChimp, then it’s not a big deal. But if you don’t, and don’t want to (we use MailPoet), you have to get away from them. We use WordPress heavily and the Mandrill WP plugin hasn’t been updated in ages. But both SendGrid and MailGun have great, actively updated WP plugins.

    Thanks or your review. We’re leaning toward SendGrid as a replacement.

  • alex says:

    Hi there,

    I have been running my transactional emails with Moosend and so far I have an awesome experience. They have an excellent support , really helpful and excellent deliverability.

  • Jeremy says:

    I told I would give my two cents into this discuss.

    My experience is only using Mandrill to send our transactional emails. However, I will say it is pretty good when sending emails within the U.S.

    If your goal is to send emails to the EU and Switzerland. This can be very painful and paying more for a mail delivery provider is a good idea.

    Another problem with Mandrill is that it shows emails as “delivered” even if the SMTP has no events. So, we went a very long time thinking all of our emails were being delivered when they were not.

    The lack of transparency with Mandrill is their biggest problem. It seems like they are more interested in keeping their perceived delivery rates high rather than helping their customer actually deliver emails successfully.

    You get what you pay for I’d say

    We are planning on switching our mail service to either sendgrid or postmarks.

  • Alyssa says:

    MailJet is not responsive at all and when your account has issues, they do not assist you! I would HIGHLY recommend using another mail server!

  • Dushyant Sharma says:

    Hello, is there an easy way to add a BCC header to all emails being sent out through Mandrill or SendGrid? Mandrill does have an option of sending a copy of each outgoing email to a specified email address, but in cases where there are, say, 5 persons in CC, it sends out 5 copies of the same email, creating a lot of redundant copies!

  • James says:

    I have been using SendGrid for the last few years, as a paid, Platinum account user. Whilst initially great, the quality of their service has decreased to a level where they are constantly embarrassing me in from of our clients. We send out marketing emails an behalf of our clients and over the last month, (November 2015) their systems have been totally unreliable. What really frustrates me is that you start a Chat with support and end up wasting an hour explaining to them why it is not working. Then you have to wait two days to get the problem fixed, if you are lucky.

    Try explaining that to a client who is sending out a limited time offer, that due to SendGrid’s again, we have , again, not been able to send out your marketing campaign.

    Seems that they are pushing untested changes to their client facing website. They Issue a change and then “Oh Gosh its not working”, so push through another hurried change and mess it up more.

    In frustration, I have reached out to their CEO via LinkedIn, but have not received any feedback from him. But then again, he is probably to busy putting out fires.

    Im not sure what has gone wrong within SendGrid. They were once an great company. Am now looking to change all my clients over as SendGrid’s incompetence is costing us money.

  • If you guys have heard of a company that dominates high-end DNS Called Dyn I can sure you having used every single one of these SMTP servers that DynECT mail is definitely not going to be a least expensive but will give you the highest delivery rate in the industry. I agree with everything said about send grid not sending to certain emails it is a shame. Keep in mind most people do not know how to set up an email box to save their life. If you choose to use DynECT DNS in addition you get an automatic enormous bonus. DNSSEC built-in to the DNS so it creates its own record without having to worry about people spoofing your mail because literally it’s one of two companies that offer this service where is it simply changes the keys with the email provided that you used because literally it’s one of two companies that offer this service where is it simply changes the keys with the email provided that you use them together. Do not get me wrong DynECT email by itself is far better than the others referenced comes with everything needed to be certain that your emails arrive in the box that they’re supposed to. To me it is ridiculous to use a service that does not give you at least a 99.9% delivery rate the only company I know of that really can do this is DynECT

  • dennis says:

    Thanks for a nice write up! I really like the mandrill app. Easy to setup, but if you send below 12000 mails per month then sendgrid is hard to beat – as it is free! Mandrill does not longer have the 12000 free mails per month. It is now 2000 mails a month, and only for one month. At least that is what I could understand by visiting the two sites.

    • Borut says:

      As of December 2015 Mandrill now only offers 2000 free mails overall, after that it’s $10 monthly subscription fee which includes 25,000 mails, so now price for 40,000 mails monthly jumped from $5.60 (as mentioned in article) to $12.95, which is considerable increase.

  • Nice, I’m Mandrill new user. Looks like, my choice seems right. Thanks for posting this.

  • Chris F says:

    As a quick heads up, as of July 2015, Mandrill no longer appears to have a free plan. The new base rate is $9.95 for the first 25,000 emails/month, then it goes up from there.


  • Dan says:

    You asked for feedback on Mailjet, and here’s my $0.02.

    We’ve been using Mailjet for a few years now to send our newsletter (~ 3500 pieces) and various informational messages to our users.

    The support (as another respondent mentioned) leaves something to be desired. While there are eventually responses, virtually NONE of our complaints (about 8) have been closed to our satisfaction. They keep asking irrelevant questions in hopes that they can wear us down.

    Over the past two months, we’ve experienced A LOT of inability to access their SMTP server for several seconds at a time, resulting in a net loss of 10% of our newsletter emails sent during the course of one day.

    We will be moving on to another provider — which is what landed me here in the first place. Thank you for the great reviews!

  • Alex says:

    We used Mandrill for our transactional E-Mails. We are now rebuilding the strategy and we are now experiencing issues in the reporting of Mandrill. Mandrill is not able to categorize different E-Mails for different categories or products. For everyone who has several products this is essential. Another problem is that Mandrill just saves their analytics for max. 90 day (if you pay extra) and we would have to save the more historic data ourselves. For that we would need to build an extra database, as this large amount of data would crash our current systems. So now im searching… Important for us is dedicated IPs, deliverability and exact reporting. Any suggestions?

    • Alex says:

      I just spoke to SendGrid, indeed very quick customer service, also they dont save data for more than 30 days. So I guess building our own database for historic data is a must.

  • Kari says:

    Thanks for the reviews on these, I also found Customer.io for transactional emails. Has anyone used this service or heard of it? It’s looking like Mandrill will be the best fit, but I don’t want to cut short on the research. Thanks!

  • CNS says:

    Great review, helped me make up my mind. Sendgrid seem amazing, but for that cost differential, Mandrill will be the provider for me. Cheers!

  • Ken Kopelson says:

    When you calculated the cost of AWS SES did you take into account that the first 62,000 messages are free? This goes WAY beyond the small 12,000 free messages with Mandrill. Just thought you should mention this, since it cuts the cost of AWS even further. That being said, AWS charges for outgoing data transfer and also for attachments. How does that stack against the others? I’d really like to see a thorough analysis of ALL costs that each of these provide. I’m sure you would have had to take those things into account in order to choose truly the best option. Anyhow, thanks for what you did provide!

  • AB says:

    We had a very poor service experience with Mandrill when trying to set up a new service. Emails to customer service were not answered in timely manner requiring multiple follow up emails. When we did get responses, they were not helpful. When we tried to provision a dedicated IP, the process took days. When we emailed support, they told us that they sent us an email response, which we didn’t see. It turns out — ironically — that this email response went into Spam folder in my Gmail account. So much for great deliverability. We are going to switch to another provider.

    • JJjJeff says:

      We’ve been using Sendgrid for over two years and their support has been excellent.

      Recently I decided to try Mandrill and had some problems. When I contacted support via their web interface, I received no response. Later I found an email address for support and finally got a “cut and paste” response that was not helpful and did not fix the issue. Despite several attempts to contact them, nothing has been fixed.

      Later on the same day (at 11:30pm), I contacted Sendgrid support about a different issue. They responded within 30 minutes (just before midnight). The response was from a real person and was a useful answer, not just boilerplate.

      Mandrill does not appear to care much about their customers.

  • RaviTeja says:

    Hi, I use Mailgun for sending transactional mails and send around 2k mails per week and we are on shared IP and so, I am facing some issues like ESP throttling issues, because of the others who are using the same as I do. I have to get my shared IP changed every time I ran into these kind of issues. Mailgun recommends to use a dedicated IP when you send more than 5k mails per day or 50k mails per week. However, I don’t send those many mails and I am blocked now, as if you use a dedicated IP and don’t send enough mails or don’t maintain the reputation, that will make my situation worse. Do you have any suggestion for this?


  • disappointed with mailjet says:

    I have to chime in and agree with the exceptionally poor, helpless, limp and anemic customer service and support given by Mailjet. Currently I experience, slow replies to tickets marked critical, and information given that is incorrect. They don’t seem to care to solve problems, or care to work to keep a customer happy, or just to keep them as a customer. It seems they couldn’t care less if you take your business elsewhere.

  • Clare says:

    Hi, i wonder whether anyone has any advice on who handles multi-language transactional emails in the best way? We use Silverpop for our commercial mailing, but their transactional system does not handle multi-language particularly well, so i am looking for an example of best practice across all global markets.



    • Andy says:

      HI Clare – did you ever figure this out? We’re looking to solve the same problem at my new startup!

    • Nils says:

      Hey Clare, any suggestions in handling the issue. We are currently using mandrill and have setup different templates of each language and using a prefix for the template name so you have en-signup, es-signup, it-signup. If you are using the API you just have to add the language prefix and you are done.

  • Matt says:

    Good overview, thanks!

  • Jay says:

    Hello Folks,

    I’m thinking of building a service oriented application. I’m not sure how to setup transactional emails. Here we are talking about AWS SES… Isn’t AWS only an outbound service provider? They don’t have the inbound mail service available. Correct me if i’m wrong… Regarding Mandril and SendGrid when they say 12,000 emails per month, does it mean 12,000 emails from a single user ID or is it overall email count? Can Mandril and Sendgrid be configurable to create different email ID’s within my application for different service providers? Please help me in understanding the mail servers better.


  • J. Alexander Curtis says:

    I have been using Mandrill as my default transactional service provider for about 2 years now. It is a great way to start with clients because most of my clients can send all the emails they need to per month for FREE and the bigger clients can send all their emails for under $10/mo with Mandrill. It is very affordable.

    Mandrill has an incredibly powerful API and great documentation. The actual mandril web application just uses their own API to do everything, so everything you can do from the web interface can be done from the API plus a lot more that isn’t even available via the web interface. So for that reason I am not sure why it was said that its API is weak. I have never ran into anything that couldn’t be done on the API.

    However, there are two things I will admit that Mandrill is weak on. First of all, customer support. They have no phone number and no live chat. You need to email them. When you email them, expect it to take a minimum of 48 hours to get back to you and sometimes as long as a week. In other words, don’t expect any significant support. When they do get back to you, they have a mindset of “if you can’t figure this out then you shouldn’t be using it or you need to hire someone that can figure it out.”

    The other weak area of Mandrill is the web interface. Yes its technically pretty to look at, but its not very usable. The navigation structure is very unnatural and confusing. There seems to be WAY too many pages considering what a simple task you are generally looking for. There are pages and sub pages and sub pages so deep, that it just doesn’t make sense. I have found the interface unusable. The good news is that once it is set up, you generally don’t need to go in there. So I only log in once or twice a year for very specific reasons.

    The last thing I wanted to address was email deliverability. I have never had a problem with deliverability on Mandrill. If you use gmail, just know that your emails will by default go into the “Updates” tab. That is where they always go, but thats also where they generally belong. My largest client sends about 900,000 emails a month through mandrill and they have never had any problems with email deliverability. I find it to be rock solid. I have been interested in trying send grid, but their pricing is much higher for what appears to be an equivalent product, so I haven’t made the leap yet. But if i switched, it would be out of curiosity, not out of necessity. I always like to know whats out there.

  • I’ve been using Mandrill for the past couple of weeks for email marketing and it gives excellent results, especially for the cost. I do sometimes look at Amazon SES pricing though and feel sorely tempted, when sending around 1m emails a week it really does begin to add up. With deliverability being pretty similar across both services it begins to make you think!

  • shai says:


    Just wanted to say that I had some bad experience with mailjet, I think they are a little bit arrogant

    I would like to get some information about the mandrill, If I use about 10-20,000 mails per months, why should I not just choose for mail chimp? And also why is it so hard to integrate Mandrill with Gmail??


  • I’m very interested in getting any other feedback on Authmailer. I have been using Sendgrid but also question their deliverabilty even though we have a 97%+ reputation.

    Authmailer’s pricing is exceptional but price does not determine performance, inversely or otherwise.

  • Jack L. says:

    I was using Mailgun, but their pricing was way too high for our service (about 1.5M mails per month = $$$). I switched first to Mandrill and then Authmailer, which offers (probably?) the cheapest pricing in high volumes. Their support is helpful, but a bit slow sometimes. It took nearly three days to setup DKIM.

    • Marcus Taylor says:

      I hadn’t heard of Authmailer, they look like an interesting option. Did you look at either SES / Sendgrid?

    • Hi Jack,

      I also had not heard of Authmailer but am now definitely considering moving across to them. Apart from the service issue you mentioned above, have you had any other challenges with Authmailer so far?


  • Anthony says:

    I just want to mention that Mandrill often provides fake delivery reports. We are developing a CRM application and recently we advised all our customers to sign-up for a mandrill account themselves and link their API key into our CRM so that we can avoid abuse issues.
    However some of our customers reported email delivery issues (e.g. their customers complained they didn’t receive any email response) so we investigated the logs found that Mandrill API reported the emails as “sent“ (not queue or whatever). The Mandrill Admin UI reported them as “Delivered”. After we conducted some simple tests we found that these accounts were actually somehow put on hold. However the customers didn’t receive any notice, the API didn’t report any error which creates confusion and as I said the mandrill user interface displays them as “delivered”.
    I’m not sure if that’s a kind of security through obscurity thing, a mandrill technical error but I find it just a bad business practice. We are now working on new plugins so that we can allow our customers to use Amazon SES or SendGrid.

    • Marcus Taylor says:

      Wow, that’s pretty poor. It’d be interesting to see whether Mandrill are alone in that or whether it’s an industry-wide issue. Keep us updated with how you get on with SES / Sendgrid.

      • angel says:

        I must agree with Anthony.
        I have found after a lot of complaints that mandrilll reported some emails as sent when they have not arrive to the inbox of the users at all.
        I am considering to move to SES API or at least have both setup so we could change easily if the problem persist.
        Also, support from Mandrill is sloowwww, several days for a reply (and not really useful one).

        For this support I prefer SES and have no support.

        Thanks for the post.

  • Hi Marcus,

    Thanks for your excellent breakdown of these providers. Glaringly absent, however, is new’ish provider Message Bus! :) Of note, I’m head of BD @ Message Bus.

    We’ve had lots of folks leaving their current providers and coming onto Message Bus’ cloud-based API-driven email platform. We’re quite different in practice than the others , providing all clients with dedicated IPs, all clients with dedicated support and a variety of human and programmatic deliverability tools that have increased open rates from 10% – 20% on average. And we are less expensive than the rest!

    Some great providers in the space and just wanted to intro Message Bus to the next generation!

    Dave Schwartz @ Message Bus
    San Francisco, California

  • JP says:

    Been using Mandrill for a lot of domains and it’s quite good (apart from being very intuitive, even for non-developers). I’ve had some frequent timeout issues with it when I use the SSL port, though.

  • Tom jones says:

    We are a startup with a significant number of transactional emails planned for specific event triggers – users upload a photo, other members of that group get notified, basic welcome messages as well as Hey, we haven’t seen you in a while types. My question is that we have highly capable off shore devs, but I am technically proficient to understand capabilities, but not a coder to implement.

    Knowing the scenario, I am leaning towards mandrill due to features and pricing, but never having created these types of emails or services before, am not sure what is involved on the dev side to make happen. Being that we have offshore dev, competent and sharp, but new to both systems, which would you choose for launch?

    I appreciate any thoughts and feedback.


    • Marcus Taylor says:

      Hi Tom,

      Sorry about the delayed response. From my own analysis and the comments, I’d recommend Sendgrid. Their API is solid and the documentation makes it relatively easy to implement. Mandrill is possibly easier to implement, but as mentioned by some of the commenters, there are a few weird issues with their service re. delivery rates, reporting etc.

    • For behavioral emails I don’t use transactional ESPs but rather use Marketing tools such as Customer.io or Route.to which provide a whole host of flexible options for sending mail rather than building that functionality into the app itself. I just have our app send customer attributes to Customer.io (via Segment.com) and then do either time or event triggered emails based on those attributes.

  • Thanks for the thorough review. I’ve been looking for a solution to recommend to my clients. I first thought of Amazon SES, but now, having read your review and the comments of others that I’m going to give Mandrill a try.

  • Frank R says:

    Mandrill is like a dream -when I was trying out the GreenArrow Engine MTA for a couple of months they threw in a trial of their Monitor product, a seed-list inbox monitoring product similar to the one offered by ReturnPath.

    Multiple tests with very similar content going to the same subscriber list showed Mandrill achieving near-100% inbox with the only exception being about 20% spam on Yahoo.

    Sendgrid on the other hand was completely blocked by AOL, 100% spam box in Hotmail and about 60% spam in Yahoo. The only success with Sendgrid was to Gmail which anyone with any experience in email marketing knows is relatively easy to inbox. Even my own Postfix installation beat out Sendgrid, with 100% inbox across the board except to Hotmail where it went 100% spam, which was quickly fixed with a support request to de-list my IPs.

    The twist is that Mandrill costs less than half of Sendgrid for infinitely better performance!!!!

    Having used Sendgrid for 3 years until stopping recently, my experience has been that they’ve gotten so many large corporate clients that they neglect smaller customers. I’m guessing that small customers get thrown on one PowerMTA which is not managed well, if at all, while big corporations get “white glove” service. Mandrill on the other hand has treated me very well despite my small $120/month spend (vs. $399/month with Sendgrid) and they’re getting my emails delivered to boot.

    • Amit says:

      Thanks Dude, Your suggestion for Mandrill have saved me from big problem.

      All Mails from Mailgun for GMAIL going in spam.
      All Mails from Sendgrid for hotmail going in spam.

      Now I switched to Mandrill , hopefully it will work for all major ESPs.


    • BOb says:

      Stop sending spam, then?

  • Mandrill sucks. Their site looks great and maybe they do things like simply send an email out to a list of user’s via their api, but if you try to do anything more complicated than that, their api falls short, and their customer service response time is not good.

    Also, they’re site is laid out so terribly. On their knowledgebase page, they have a section for getting a hold of mandrill. It has a blurb that reads “In the footer of the Mandrill web application is a Supportbutton.” Why can’t they just have a damn support button right there?

    Also, the navigation is the clumsiest i’ve seen in 2014. The left nav changes depending on where you’re at. Sometimes there’s nothing there at all. Sometimes the link you’re needing is in the top nav, sometimes in the left, sometimes in your individual settings.

    • Paul says:

      Completely agree about their support being hard to find and slow. Mailchimp are slow to respond too. Mandrill routes everything back to their extremely basic knowledge base canned answers and makes it hard to figure out how to send them a question. Ironic, they seem to be afraid of getting emails.

  • John says:

    Hi, I’m confused about Mandrill being better than SES when they are using SES to send out emails. Any thoughts?

  • szunyi says:

    My favourite is the “Mandrill”. Fast and precise! Never deliver my emails to the SPAM.

    My biggest disappointment is the “Amazon SES”, slow and/or go my emails to SPAM in Gmail…

    • Anthony Chambers says:

      Agreed SES emails nearly always go to Spam, Mandrill typically land in the email box providing your email isnt spammy.

    • kevin says:

      Mandrill is built on top of SES, so your comment doesn’t make any sense. SES is not slow, and Mandrill sends through SES – it just adds a pretty interface and more functionality.

      • Hi Kevin,

        See the comment below linking to the Mandrill FAQ – Mandrill say that they depreciated their Amazon SES integration in September 2012 to begin using their own service.

  • Alexandre Cabanis says:

    Hi Marcus,

    You asked for someone’s return on experience about Mailjet. Well, I hope Mailjet CMO’s feedback count for one…
    To answer your question about how we stand out from Sendgrid, I would say:
    – International deliverability support: not the shiniest asset, but a very effective one for every company that expect their emails to reach Gmail and Yahoo inboxes but also Orange, BT, Telekom… Our 24/7 customer support is very reactive on this question among others and in 4 languages… but granted, through tickets and not emails.
    – User-friendly interface, shiny asset here. We’re glad to be included in this transactional ESP comparison, but we do offer an all-in-one product, also meant to meet e-marketers expectations about sending, analysing and enhancing their newsletters and notifications. A neat layout is compulsory to meet that goal.

    I hope this helps and please make sure to check again our product in the coming months.


    • Thanks for weighing in, Alexandre.

      Interesting point re. having high deliverability to Orange / BT / Telekom addresses. Out of interest, does this apply also to email addresses in countries such as China or Russia where people use Chinese / Russian email providers (i.e. not Google, Yahoo etc)? That’s quite a strong selling point if so.


      • Alexandre Cabanis says:

        It does apply to Russia also, indeed. As for the rest of the world, we cannot complain about deliverability troubles so far.

    • Ram Krishna says:

      Hi Alexandre,

      This is a long time customer of Mailjet. While I am reasonably satisfied with your service in general, your response process definitely needs to be improved.
      I have one ticket right now which has been open for a while now: n°170874

      The simple ones are attended too quick enough but if the issue is slightly complicated, it just seems to go into limbo or attended to over days. In today’s world where our customers expect turnaround time in minutes, this becomes a problem.

      Regret that I have had to call this out on a public forum but this is something you definitely need to look into. Do see if the above ticket number can be addressed by your team.


      • Alexandre Cabanis says:

        Hi Ram, the circumstances are temporary and we apologize for that.

        Besure that support has given the greatest consideration to your tickets and post and will give you a thorough answer as soon as possible

    • Pulkit says:

      I signed up for Mailjet. The account confirmation email they sent me ended up in the spam folder of my Zoho mail account. I deleted it and abandoned signup :)
      Seriously, get your act together Mailjet.

    • Benoit says:

      What a joke!

      I was one of you customers for about 15 months. One day, someone in my team send an email to herself with the title “5.15” to remember a price.

      The result was that Mailjet considered us as very dangerous spammers, shutting down all our emails without any notice during a key period for us. As we cannot call anyone, we contacted the support. 5 very long days before they say ” you are a spammer” without any precision. I kept asking and asking “which email??”. Of course they never could find any spam from us and finally agreed 2 weeks after that is was a mistake.

      When you work with coftware wihtout any decent human support, you get the worst service ever. Search on the web, you will find many people having bad experiences with mailjet.

      You really praise yourself and your company?

  • Hiroshi Sasakura says:

    Very nice review. Thank you for your information.