Posteo vs Proton Mail
We give Posteo a 2.6 GPA and Proton Mail a 3.2, out of 4.0. Posteo grades higher on value for money. Proton Mail grades higher on the free plan and ease of use. They get the same grade on features and platforms.
Price, platforms and features side by side. The table says where each price was read and when.
Proton Mail
End-to-end encrypted email service based in Switzerland
Free plan · from $3.99/mo
How we grade them
| 2.6GPAPosteoGood | 3.2GPAProton MailVery good | |
|---|---|---|
| Value for money | A€1 a month, prepaid, for 4 GB of storage, 3 aliases, 3 calendars, an address book and notes. The middle for email tools here is about $9. Extra storage is €0.25 per GB a month if you need it. The minimum top-up is €12, which is about one year's fees. | BMail Plus is $3.99 a month on the yearly plan, for 15 GB, 10 addresses and your own domain. Fair for private email, but Gmail and Outlook give you 15 GB for nothing. |
| Free plan and trial | FNothing is free. There's no free plan and no trial account, so you pay before you see the inbox. Credit is refunded in full if you cancel within the first month, which softens it. A refund isn't a trial, though. | BFree for good with no ads, which is rare. But it's tight: one address, up to 1 GB and 150 sent messages a day. The desktop app is for paying customers. |
| Features | BEverything you store can be encrypted, PGP and S/MIME work inside webmail through plug-ins, and calendars and contacts sync over CalDAV and CardDAV. Login takes passkeys and two-factor codes. Solid, private basics. But custom domains are not supported, and it offers no cloud storage. | BEncryption you never have to think about, tracker blocking, throwaway aliases, a calendar and snooze. But other mail apps only connect through Bridge, on a paid plan. |
| Ease of use | BNo rating on record, so a B is our ceiling. There's one account and one price, so there's nothing to choose between, and registration asks for no name or address. PGP in webmail does mean adding the Mailvelope plug-in. | A4.8 from about 48,500 App Store ratings, a touch above Gmail's own app. It works like any inbox, and Easy Switch brings your old mail over for you. |
| Platforms and integrations | BWebmail and a web app, with no phone or desktop apps of its own on record. It works in other mail apps such as Thunderbird and Outlook over IMAP or POP3, calendars and contacts sync over CalDAV and CardDAV, and notes can be synchronized with Apple Notes. | BWeb, Mac, Windows, Linux, iPhone and Android, so every device is covered. But the desktop apps need a paid plan, and the Linux one is still a beta. |
| Best for | a private mailbox for €1 a month | email your provider can't read |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Posteo and Proton Mail. How we grade
Where they differ
- Posteo starts at €1 per month, prepaid (minimum top-up €12). Proton Mail starts at $3.99 per month, billed every 12 months ($47.88); $4.99 billed monthly.
- Proton Mail has a free plan. Posteo does not.
- Only Proton Mail lists macOS, Windows, Linux, iOS and Android apps.
- Posteo also covers notes.
In commonWebOpen sourceEnd-to-end encryptedCalendarEmail client
At a glance
| Posteo | Proton Mail | |
|---|---|---|
| Pricing | Paid | Free plan |
| Starts at | €1 per month, prepaid (minimum top-up €12) | $3.99 per month, billed every 12 months ($47.88); $4.99 billed monthly |
| Free plan | None | Proton Free: 1 email address, up to 1 GB of mail storage (500 MB until the setup steps are completed), a limit of 150 sent messages a day and 3 personal calendars. |
| Free trial | None listed | None listed |
| Web | ||
| macOS | ||
| Windows | ||
| Linux | ||
| iOS | ||
| Android | ||
| Made by | Posteo e.K. | Proton AG |
| Price read from | posteo.de | proton.me |
| Checked | Oct 6, 2026 | Oct 4, 2026 |
Who each one suits
Posteo
- People who want a low-cost, ad-free mailbox they pay for directly
- Signing up without handing over a name, address or phone number
- Buyers who care about green energy and a company financed only by its users
Proton Mail
- People who want an email provider that cannot read their messages
- Anyone moving off Gmail, Outlook or Yahoo who needs to import old mail
- Users who want email, VPN, passwords and storage from one vendor
Worth knowing
Posteo
- Custom domains are not supported; addresses use Posteo's own domains such as posteo.de, posteo.net or posteo.com.
- There is no free plan and no trial account, though credit is refunded in full if you cancel within the first month.
- Payment is prepaid in euros, with a minimum top-up of €12, which is about one year's fees.
- It is used through webmail and a web app or through other mail apps over IMAP or POP3, and it offers no cloud storage.
Proton Mail
- The free plan is limited to 1 address, up to 1 GB of mail storage and 150 sent messages a day.
- Custom domains and IMAP/SMTP access through Bridge need a paid plan.
- The desktop apps need a paid plan; free accounts get a 14-day trial of them, and the Linux app is labeled beta.
- Buying in the iOS app costs more: the US App Store lists Mail Plus at $5.99 monthly, against $4.99 on Proton's site.
Key features
Posteo
- One flat-priced account
- €1 a month covers email with 4 GB of storage, 3 aliases, 3 calendars, an address book and notes. Storage can grow to 75 GB and aliases to 25 for small monthly add-on fees.
- Encryption of stored data
- Crypto mail storage encrypts saved email, attachments, metadata and notes, and the address book and calendar can each be encrypted with your own password at the press of a button.
- End-to-end encryption in webmail
- PGP through the Mailvelope plug-in and S/MIME through Posteo's own plug-in work inside the webmail interface, and incoming mail can be encrypted with either.
- Sign-up without personal details
- Registration asks for no name or address, payment data is kept separate from email accounts, and credit can be added by bank transfer, PayPal, credit card or cash.
- Calendar, contacts and notes
- Calendars sync over CalDAV and can be shared read-only by ICS link, contacts sync over CardDAV, and notes can be synchronized with Apple Notes.
- Passkeys and login protection
- Login supports two-factor authentication (TOTP), up to 5 passkeys and up to 5 app passwords. An extra protection mode blocks access from external programs over IMAP.
Proton Mail
- End-to-end and zero-access encryption
- Messages are encrypted so that only you can read them. Proton states that not even it can read your email.
- Tracker blocking and aliases
- Blocks the email trackers that report what you open and click. Hide-my-email aliases keep your real address off sign-up forms: 10 on Free and Mail Plus, unlimited on Proton Unlimited.
- Custom domains and extra addresses
- Mail Plus supports 1 custom email domain and up to 10 addresses. Proton Unlimited raises that to 3 domains and 15 addresses.
- Easy Switch import
- Imports existing mail from Gmail, Outlook, Yahoo or Apple accounts. The import assistant is included on the free plan.
- Proton Mail Bridge
- Paid accounts can use the Bridge app to read and send encrypted mail in Microsoft Outlook, Mozilla Thunderbird or Apple Mail over IMAP and SMTP.
- Calendar and scheduling tools
- Proton Calendar is included, with 3 personal calendars on Free and up to 25 on Mail Plus. Mail also supports scheduled sending, undo send and snooze.
Plans
Posteo
Email account€1
per month, prepaid from account credit
4 GB of storage, 3 aliases, 3 calendars, address book and notes. Extra storage costs €0.25 per GB a month and extra aliases or calendars €0.10 each.
Proton Mail
Proton Free$0
1 address, up to 1 GB of mail storage, 150 sent messages a day, the Easy Switch import tool and 3 calendars.
Mail Plus$3.99
per month, billed every 12 months ($47.88); $4.99 billed monthly
1 user with 10 addresses, 15 GB of storage, 1 custom domain, unlimited folders, labels and filters, and Bridge for IMAP/SMTP clients.
Proton Unlimited$9.99
per month, billed every 12 months ($119.88)
500 GB of storage, 15 addresses and 3 custom domains, bundled with Proton's VPN, password manager and cloud storage.
Ways to pay less
Posteo
No public discounts listed.
Proton Mail
- Annual discount
20% off Mail Plus on the 12-month plan
Proton's pricing page lists Mail Plus at $3.99 a month when billed every 12 months ($47.88), against $4.99 billed monthly.
