Proton Mail vs MailerSend Comparison (2026)

Compare Proton Mail vs MailerSend email services. In-depth analysis of features, pricing, security, privacy, and storage to find the best email provider for your needs.

Forward Email Team
Written by
Forward Email TeamVerified
Published
4/1/26
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.MailerSend

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.

MailerSend

Intuitive email API and SMTP
"Intuitive email API and SMTP"
  • Hardenize Test
  • Internet.nl Site Test
  • Internet.nl Mail Test
  • Mozilla HTTP Observatory Grade
  • Qualys SSL Labs SSL Server Test
$3.99/moPricing$288/yr
15 GBStorageNo MailerSend does not support storage
25 MBAttachments25 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-inIMAPNo
❌ Proton Mail does not support POP3POP3No
NoAPIYes
⚠️ 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. According to their website: Secure email that protects your privacy

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

MailerSend

MailerSend is a closed-source email service. Its description from its website is: Intuitive email API and SMTP

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

Compare Proton Mail with 78 email services