The bureau · Email
Open-source private email providers
3 providers here publish open-source code you can inspect. Tuta rates highest. Open-source clients (and ideally servers) let independent researchers verify that the encryption works as claimed, rather than taking the provider’s word for it. It is a trust signal, not a privacy guarantee on its own.
3 matches, ranked
Which private email providers are open source?
Tuta
The strongest zero-access model in the category - it encrypts the subject line, attachments, contacts and calendar, not just the body, so it cannot read your stored mail. Genuinely no-KYC. A 2020 German court order forced monitoring of named accounts going forward, but even then it could not decrypt existing end-to-end-encrypted mail.
- 1KYC
- No phone
- Zero-access
Proton Mail
The market leader, and the clearest lesson that private is not the same as anonymous. Signup needs no phone, and stored message bodies are zero-access encrypted - but documented cases show that IP, payment and recovery data are reachable under a Swiss court order, and subject lines are not encrypted.
- 2KYC
- Zero-access
Riseup
A no-KYC, invite-based activist mail collective that moved to encrypted storage after being served two sealed FBI warrants under a gag order in 2016 - which it complied with rather than face contempt, and its warrant canary lapsed. Mission-trusted, but US jurisdiction is the structural weakness.
- 1KYC
- No phone
Ask the bureau
Open source — questions
Does open source make email more private?
Indirectly. Open code lets researchers audit whether the encryption and no-logging claims hold, which is why the strongest providers publish theirs. But open source alone does not stop a provider from logging metadata or handing it over - judge it alongside jurisdiction and track record.
Browse the full email directory or read the methodology.