Posteo vs N‑able Mail Assure Comparison (2026)

What are the differences between Posteo 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 Posteo. We also support webmail: https://mail.forwardemail.net

Email Service Comparison

20 facts in comparison
Posteovs.N‑able Mail Assure

Posteo

Green, secure, ad-free
"Green, secure, ad-free"
  • 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
€1/moPricingRequires you to talk to a sales team
2 GBStorageRequires 3rd party
50 MBAttachmentsDepends on inbound/outbound (e.g. 10 MB)
NoOpen-SourceNo
NoSandboxed Encryption No
NoUnlimited DomainsNo
NoUnlimited AliasesNo
NoTTI No
YesSMTP❌ Requires 3rd party
YesIMAP❌ Requires 3rd party
YesPOP3❌ Requires 3rd party
NoAPIYes
⚠️ Opt-inE2EE No
YesOpenPGP No
YesWKD No

Email Service Screenshots

Closed-source

Posteo

Posteo is a closed-source email service. According to their website: Green, secure, ad-free

Posteo is a closed-source email service.
Photograph by Forward Email
Visit Website
Closed-source

N‑able Mail Assure

N‑able Mail Assure is a closed-source email service. Its description from its website is: Email protection to help you secure and scale

N‑able Mail Assure is a closed-source email service.
Photograph by Forward Email
Visit Website

Compare Posteo with 78 email services