Proton Mail vs 123 Reg Comparison (2026)

What are the differences between Proton Mail and 123 Reg?

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 Proton Mail. We also support webmail: https://mail.forwardemail.net

Email Service Comparison

20 facts in comparison
Proton Mailvs.123 Reg

Proton Mail

Secure email that protects your privacy
"Secure email that protects your privacy"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
vs.

123 Reg

Professional email that shows you mean business
"Professional email that shows you mean business"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
$3.99/moPricing£35.88/yr
15 GBStorage10 GB
25 MBAttachments30 MB
❌ Proton Mail claims to be open-source, but their back-end actually is closed sourceOpen-SourceNo
NoSandboxed Encryption No
NoUnlimited DomainsNo
NoUnlimited AliasesNo
NoTTI No
❌ Requires you to download Proton Mail Bridge and forces vendor lock-inSMTPYes
❌ Requires you to download Proton Mail Bridge and forces vendor lock-inIMAPYes
❌ Proton Mail does not support POP3POP3Yes
NoAPINo
⚠️ Proton Mail rewrites your emailsE2EE No
YesOpenPGP No
YesWKD No

Email Service Screenshots

Closed-source

Proton Mail

Proton Mail is a closed-source email service. Their official description reads: Secure email that protects your privacy

Proton Mail is a closed-source email service.
Screenshot by Forward Email
Go to site
Closed-source

123 Reg

123 Reg is a closed-source email service. Their official description reads: Professional email that shows you mean business

123 Reg is a closed-source email service.
Photo by Forward Email
Go to site

Compare Proton Mail with 78 email services