When comparing SendGrid vs Postmark, the Slant community recommends Postmark for most people. In the question“What are the best transactional email services?” Postmark is ranked 2nd while SendGrid is ranked 5th. The most important reason people chose Postmark is:
Postmark is designed to send transactional messages. It specifically warns users not to use it to send weekly newsletter -- this way the emails sent by Postmark are less likely to be marked as spam, increasing the likelihood of your messages reaching the users.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Excellent analytics
SendGrid offers amazing analytics and reports. You can check which messages are delivered, which are marked as spam and much more. SendGrid also lets you download the data in order to look through it locally.
Pro Great support for beginners and experienced users
If you are just getting started with email marketing and transactional emails or if you get stuck somewhere, SendGrid includes amazing videos and guides to help you work out any problem you may have. What's more, it also has phone, chat and email support available 24/7.
Pro Both newsletter and transactional emails
Usually when choosing a service to send your application's emails you need two. One to send the newsletter or news and promotions from the marketing team and the other to send you application's automatic emails and messages.
With SendGrid you don't have to choose two because it doubles both as a transactional and marketing platform at once.
Pro Has a free tier
12,000 free e-mails per month.
Pro Easy to use API
The API is very easy to use and very intuitive. On top of that, the documentation for the API is complete and very useful, covering everything you need to know.
Pro Messages are unlikely to be marked as spam
Postmark is designed to send transactional messages. It specifically warns users not to use it to send weekly newsletter -- this way the emails sent by Postmark are less likely to be marked as spam, increasing the likelihood of your messages reaching the users.
Pro DMARC
Supports domain-based message authentication which helps to prevent spammers from using your domain to send email without your permission.
Pro Detailed analytics
Postmark offers very detailed analytics for your emails. For starters, it stores 45 days worth of email logs where you can search to find out which emails were sent, received, who received them, who read them and who marked them as spam.
There are also recipient profiles which keep track of everyone who gets your emails, complete with a list of messages that they have opened, deleted or marked as spam.
Pro Messages are Saved for 45 Days
All outgoing messages are saved for 45 days so you can see what you're sending to who. This is important if you are sending any dynamic content in your emails.
Pro Multiple server locations
Postmark has 5 server locations around the world (3 in the US, 1 in Amsterdam and 1 in SIngapore). This way emails will be sent fast regardless of where your users are.
Cons
Con Port 2525 is not encrypted
Most cloud providers block ports 25, 465, and 587. Port 2525 is commonly open but SendGrid only allows unencrypted messages via that port.
Note: There are also so some certificate issues (see https://support.sendgrid.com/hc/en-us/articles/200182008-Certificate-verification-failed-for-smtp-sendgrid-net)
Con Poor deliverability of emails
Con Not suitable for people without a technical background
There are some features which are missing by default from SendGrid (sign-up forms or follow-up messages just to name a few). In order to implement those in your emails, you need to know how to program because you have to code them yourself through SendGrid's API.
Con No sandbox/test mode
Does not support test keys that can be used to check integration with SendGrid and that cannot be used to send real e-mail out. It means that either you don't cannot verify that your integration with SendGrid works during development, or you have to use real credentials which should not be shared widely across your team.
Con Can't view contents of sent emails
They do not capture the sent emails. This means you cannot check that the email was sent correctly, and it makes it harder to debug issues that arise.
Con Expensive
Postmark are one of the most expensive (if not the most expensive) services in the market, at $1.5 per 1000 emails.
