sendgrid vs postmark

Question

I am evaluating 3rd party services to handle our webapps email.

Requirements:

• Tracking bounces
• HTML email
• Customer headers
• Incoming email queue (Post email to some URL?)
• Spam filtering of incoming email
• Handle SMTP server issues, authentication, whitelisting, keys, etc
• Support attached images as well as embedded images from an URL
• Reasonable performance (don't have hard numbers but most email should pass in under 15 secs)
• Cheap

I ran across postmark and sendgrid, I guess there are more. What do you think?

Answer 1

Check out SocketLabs Email On-Demand. http://www.socketlabs.com/od. They have been doing email delivery forever and have a robust reporting system and API.

Answer 2

The email services I have come across with robust API integration are:

• SendGrid
• CritSend
• PostMark
• SocketLabs
• MailChimp

I'm using CritSend for my web app (approx. 25000 users) and it works well. SendGrid and CritSend are priced very similarly, though CritSend is basically a buy credits then use them model, whereas SendGrid requires you to pay a basic monthly fee and then pay extra if you exceed your quota. It works out basically the same, but with SendGrid you have to pay a minimum amount each month (which still counts towards email credits) whereas CritSend has no minimum. Both services offer free credits on signing up then charge around $1 per 1000 emails sent.

I haven't used PostMark, though their pricing is 50% more expensive than SendGrid and CritSend. Their presentation is much more professional/refined than CritSend or SendGrid.

SocketLabs I only heard of because of Brian's answer to this question.

MailChimp have a robust API but are more focussed on campaign sending than individual emails. Their presentation, reporting and setup are all very professional and user friendly.