Heimdal vs addy.io Comparison (2026)

What are the differences between Heimdal and addy.io?

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 Heimdal. We also support webmail: https://mail.forwardemail.net

Email Service Comparison

20 facts in comparison
Heimdalvs.addy.io

Heimdal

One Platform. Total Security.
"One Platform. Total Security."
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
vs.

addy.io

Protect your real email address using email aliases
"Protect your real email address using email aliases"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
Requires you to talk to a sales teamPricing$4/mo
Requires 3rd partyStorageNo addy.io does not support storage
UnknownAttachments25 MB
NoOpen-SourceYes
NoSandboxed Encryption No
NoUnlimited DomainsNo
NoUnlimited AliasesYes
NoTTI No
❌ Requires 3rd partySMTPNo
❌ Requires 3rd partyIMAPNo
❌ Requires 3rd partyPOP3No
YesAPINo
NoE2EE No
NoOpenPGP No
NoWKD No

Email Service Screenshots

Closed-source

Heimdal

Heimdal is a closed-source email service. Their official description reads: One Platform. Total Security.

Heimdal is a closed-source email service.
Photo by Forward Email
Go to site
Open-source

addy.io

addy.io is an open-source email service. Their website says: Protect your real email address using email aliases

addy.io is an open-source email service.
Screenshot by Forward Email
Go to site

Compare Heimdal with 78 email services