Postmark vs N‑able Mail Assure Comparison (2026)

What are the differences between Postmark and N‑able Mail Assure?

Forward Email Team
Written by
Forward Email TeamVerified
Published
2/1/26
Time to read
Less than 5 minutes
We recommend Forward Email as the best alternative to Postmark. We also support webmail: https://mail.forwardemail.net

Email Service Comparison

20 facts in comparison
Postmarkvs.N‑able Mail Assure

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.

N‑able Mail Assure

Email protection to help you secure and scale
"Email protection to help you secure and scale"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
$15/moPricingRequires you to talk to a sales team
No Postmark does not support storageStorageRequires 3rd party
10 MBAttachmentsDepends on inbound/outbound (e.g. 10 MB)
NoOpen-SourceNo
NoSandboxed Encryption No
NoUnlimited DomainsNo
NoUnlimited AliasesNo
TTI TTI No
YesSMTP❌ Requires 3rd party
NoIMAP❌ Requires 3rd party
NoPOP3❌ Requires 3rd party
YesAPIYes
NoE2EE No
NoOpenPGP No
NoWKD No

Email Service Screenshots

Closed-source

Postmark

Postmark is a closed-source email service. Their website says: The email delivery service that people actually like

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

N‑able Mail Assure

N‑able Mail Assure is a closed-source email service. Their website says: Email protection to help you secure and scale

N‑able Mail Assure is a closed-source email service.
Screenshot by Forward Email
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Compare Postmark with 78 email services