All in all before we had even launched our application they had thrown nearly 200,000 free email credits at us. We hadn't even provided a credit card yet.
Considering at launch we were sending about 2,000 emails per month on a busy month we joked that we would never have to pay these guys.
Come a year and a half later we're sending a lot more than 2k emails per month and we're just about out of credits. At this point Postmark had become so ingrained in our applications (we made heavy use of their SDKs and templates) there wasn't any easy way to switch if we wanted to.
While we thought they were the fools for giving us such an obscene amount of free credits, they ultimately won in the long game and that company is still using (and now paying) Postmark.
All of that said, Postmark IS fantastic. I use them for every project where I need to send or receive mail, and I wouldn't consider anyone else. Highly recommend them.
Spent over 1 year cruising through their free credits, now happily paying a couple hundred a month without a second thought.
It's really intuitive and easy-to-use to see errors, read text of emails, and so forth.
Side note: It's neat to see people come out of the woodwork on this thread for Postmark, which is normally one of those products consumed so quietly, and under-appreciated. I bet their team is really happy to see this. :)
Also their deliverability is excellent and when there are deliverability issues, it's easy to find exactly why. The logs also surface the info we need to prove what actually happened during a nondelivery event. ("Here is the actual log line from your MX server rejecting the mail we sent.")
For small near-zero-budget projects, I still use Amazon SES. It's Good Enough for most uses and nobody else with even decent deliverability can touch them on price. All my hobby projects combined are billing well under $1/mo for SES usage.
SES is also decent for some very specific inbound email use cases. If you need to receive email from some system that doesn't have a real webhooks type outbound API, but does have robust email notifications, and send the body to a Lambda function that parses it and makes the API call that system ought to have just made in the first place.. SES is perfect. (And unfortunately all the major systems I work with that process inbound email are stuck needing an IMAP connection - if I was able to use an API based inbound email receipt scheme, and needed to receive mail from various domains, I'd consider Postmark for the better diagnostics and logging.)
Link to postmark since it’s kind of hard to find on google: https://postmarkapp.com/
They're shutting down accounts without any notice. It doesn't matter how many emails you sent, that you have 0 spam complaints, extremely low bounce rate ... on the first issue they're banning your account.
We used them to notify our customers when new people sign up on their portal so we included details about those users, including the website. We got JUST ONE, SINGLE .tk domain in the email content and they blocked our account completely. We were also on their Premier plan.
No notice before-hand, no warning, nothing.. they simply blocked the account and haven't activated it back even after numerous requests. They couldn't point to any document that stated their policies and what rules we should follow or why they banned us.
tl;dr. Stay away from Sparkpost, they ban your account without notice.
Our account (that we had been using for 6 months) was locked right after we paid a bit over $200 for October.
We filled a ticket and gave them all the info they requested. Eventually the reply was a template that didn't explain anything. They also refused to refund the remaining credits.
Here the nice rejection email:
Thank you for your interest in SparkPost. We strive to offer the very best email service, and to that end, we maintain a strict anti-abuse messaging policy.
Because we cannot offer you the high deliverability you would expect from SparkPost, we must decline to provide our services. We wish you the best in your future business endeavors.
Sendgrid and Sparkpost are the only two I know of doing this correctly at the moment.