Postmark vs AT&T Comparison (2025)

What are the differences between Postmark and AT&T?

Forward Email Team
Written by
Forward Email TeamVerified
Published
7/1/25
Time to read
Less than 5 minutes
We recommend Forward Email as the best alternative to Postmark.

Email Service Comparison

20 facts in comparison
Postmarkvs.AT&T

Postmark

The email delivery service that people actually like
"The email delivery service that people actually like"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
vs.

AT&T

AT&T Mail is now Yahoo Mail
"AT&T Mail is now Yahoo Mail"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
$15/moPricing$5/mo
No Postmark does not support storageStorage5000 GB
10 MBAttachments25 MB
NoOpen-SourceNo
NoSandboxed Encryption No
NoUnlimited DomainsNo
NoUnlimited AliasesNo
TTI TTI No
YesSMTP❌ No longer supported
NoIMAP❌ No longer supported
NoPOP3❌ No longer supported
YesAPINo
NoE2EE No
NoOpenPGP No
NoWKD No

Email Service Screenshots

Closed-source

Postmark

Postmark is a closed-source email service. Its description from its website is: The email delivery service that people actually like

Postmark is a closed-source email service.
Photo by Forward Email
Go to site
Closed-source

AT&T

AT&T is a closed-source email service. Their official description reads: AT&T Mail is now Yahoo Mail

AT&T is a closed-source email service.
Screenshot by Forward Email
Go to site

Compare Postmark with 78 email services