# Delta Chat

> Source: https://fuckyc.org/services/deltachat/
> Website: https://delta.chat/
> Categories: Messaging
> KYC: none — A messenger that uses email as transport. Identity is whatever email account you connect; the operator at delta.chat does not run accounts. Chatmail servers (low-friction email accounts purpose-built for Delta Chat) exist and require no signup data.
> Status: active
> Jurisdiction: independent open source (merlinux GmbH, Germany)
> Fiat on-ramp: no
> Payment methods: donation
> Founded: 2017
> Open source: yes
> Custodial: no
> Last verified: 2026-01-01

## Verdict

Delta Chat is the email-as-transport messenger. Pair it with a Chatmail server or a privacy email provider and you have a messenger that uses standard mail infrastructure. The architecture is unusual but useful — federation is free, the wire format is SMTP, and the encryption is Autocrypt. Best fit for users who want a federated chat that does not require running a new protocol's servers.

## Strengths

- Uses standard email under the hood — federates with anything that speaks SMTP/IMAP.
- Autocrypt + end-to-end encryption between Delta Chat users.
- Chatmail servers offer free, no-signup email accounts purpose-built for chat use.

## Caveats

- Privacy properties depend on the email server you choose; using Delta Chat over a KYC mail provider doesn't deliver the no-KYC posture.
- First-time key exchange requires that the other party also be on Autocrypt or in-app.
- Facts need re-verification by operator (last seeded 2026-01).

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## What Delta Chat is

A messenger client that uses email (SMTP/IMAP) as transport, with Autocrypt-based end-to-end encryption between Delta Chat users.

## Threat-model fit

When email federation is the right substrate — you already have, or can create, a no-signup mail account.

## Sources

- [Delta Chat help](https://delta.chat/en/help) — accessed 2026-01-01
- [Delta Chat source](https://github.com/deltachat) — accessed 2026-01-01