Proton Mail review

Proton Mail is the pick for iPhone users who want an inbox that its own provider cannot read. Messages are stored with zero-access and end-to-end encryption, emails between Proton users can only be read by sender and recipient, and the open-source apps use OpenPGP and are independently audited. You can send password-protected emails to people outside Proton, and the app blocks email trackers and flags phishing. Offline mode lets you read and write mail without a connection. The free plan gives a @proton.me or @protonmail.com address with 1 GB of storage. Mail Plus raises that to 15 GB with 10 addresses and one custom domain; on Proton's US pricing page it was billed at $29.88 for the first year and $47.88 a year after that when we checked in November 2026, while the App Store charges $5.99 a month. The main limit is that the app only opens Proton accounts, so it cannot replace Apple Mail for a Gmail or iCloud address.

Who it is for

privacy-focused users who want encrypted email

Price

Free plan with 1 GB; Mail Plus $2.49 a month for the first year billed at $29.88, then $47.88 a year.

Billed at $29.88 for the first 12 months, then renews at $47.88 every 12 months.
Quoted from the vendor pricing page on November 13, 2026.

Key features

• Zero-access and end-to-end encryption; Proton says it cannot read or scan your messages
• Password-protected emails to people who do not use Proton
• Offline mode to read, write and organize mail without a connection
• Easy Switch moves mail over from Gmail
• Mail Plus adds 15 GB of storage, 10 addresses and 1 custom domain

Strengths and weaknesses

• Strength: Free @proton.me address with no ads, according to the App Store listing
• Strength: Open-source apps that are independently audited
• Strength: Built-in email tracker blocking and phishing alerts
• Weakness: Free storage is 1 GB
• Weakness: Only works with Proton accounts, not Gmail or iCloud logins
• Weakness: Monthly Mail Plus costs $5.99 in the App Store versus $4.99 on Proton's site

Key facts

• Free plan: Yes, 1 GB storage
• Mail Plus: 15 GB, 10 addresses, 1 custom domain
• Encryption: End-to-end, OpenPGP
• Based in: Switzerland

Where it ranks

Proton Mail is No. 5 in our Best Email Apps for iPhone verdict.