Comparison
Signal vs Telegram
Signal: The gold-standard E2EE messenger: open-source, independently studied, post-quantum, and run by a nonprofit that has proven in court it holds almost no data — but it still ties your account to a phone number and runs on central servers. · Telegram: A fast, feature-rich cloud messenger with a huge user base — but chats are end-to-end encrypted only when you manually start a "Secret Chat," so by default Telegram itself can read your messages.
Bottom line: For private messaging, Signal is the clearer choice: it is end-to-end encrypted by default for all chats and calls, is fully open-source and independently studied, holds almost no user data, and has already shipped post-quantum cryptography — there is no setting to forget to turn on. Telegram is genuinely excellent at what it optimizes for — speed, huge group/channel communities, bots, and large file transfers (up to 2 GB free, 4 GB with Premium) — but its default chats are not E2EE, so if confidentiality matters you must remember to start a Secret Chat for every sensitive one-on-one conversation, and you simply cannot get E2EE for groups or channels at all.
Signal and Telegram are often mentioned in the same breath as "secure messengers," but they make fundamentally different promises. The core difference is what's encrypted by default and who can read it. On Signal, every one-to-one and group chat is end-to-end encrypted using the open-source Signal Protocol (X3DH + Double Ratchet), now extended with post-quantum protections — PQXDH for the handshake and the SPQR "Triple Ratchet" for ongoing messages — so Signal's servers cannot read message content. On Telegram, ordinary "cloud chats" are encrypted only between your device and Telegram's servers (MTProto 2.0); they are stored on Telegram's infrastructure in a form Telegram can decrypt. Telegram is end-to-end encrypted only inside Secret Chats, which are opt-in, limited to one-on-one conversations, and tied to a single device — meaning groups, channels, and your default conversations are not E2EE.
Beyond encryption defaults, the two diverge on identity, key custody, and governance. Both require a phone number to register and both run on centralized servers. But Signal is operated by a U.S. nonprofit (the Signal Foundation) that minimizes the data it holds — a posture it has demonstrated in court by being able to produce almost nothing in response to subpoenas — whereas Telegram is a feature-rich commercial platform (legal entity in the British Virgin Islands, operations centered in Dubai) that retains far more, since most chats live decryptable on its servers. The practical question isn't "which is encrypted" but "what is encrypted, for whom, by default, and what does the operator keep."
The facts, side by side
| Signal | Telegram | |
|---|---|---|
| End-to-end encrypted by default | Yes | No Default 'cloud chats' use only client-server (server-client) encryption — Telegram's servers can decrypt and store them. End-to-end encryption applies ONLY to opt-in Secret Chats, which are 1:1 only, must be started manually, are not available in the desktop/web clients, and do not sync across devices. Group chats and channels are never E2EE. |
| Encryption protocol | Signal Protocol: X3DH + Double Ratchet with AES-256-GCM, now extended by PQXDH (handshake) and the Triple Ratchet / SPQR (post-quantum ratchet) Signal's classic stack is X3DH key agreement + the Double Ratchet, with AES-256 in CBC/HMAC historically and AES-256-GCM AEAD. In 2023 Signal added PQXDH (X25519 + CRYSTALS-Kyber/ML-KEM-768) to the initial handshake, and on Oct 2, 2025 shipped the Sparse Post-Quantum Ratchet (SPQR), combining the Double Ratchet with an ML-KEM-768 ratchet into a hybrid 'Triple Ratchet.' | MTProto 2.0 (custom): AES-256-IGE + SHA-256 for client-server cloud chats; Diffie-Hellman + AES for opt-in Secret Chats MTProto is a home-grown protocol that has been widely criticized by cryptographers (e.g. Matthew Green) for 'rolling its own crypto' and using the unusual AES-IGE mode. Academic analyses exist (e.g. a 2021 ETH Zurich symmetric-protocol study) but there is no comprehensive independent audit of the full live system. |
| Post-quantum key exchange | Yes Post-quantum protection is hybrid (classical + ML-KEM-768) and is being rolled out automatically; older clients downgrade gracefully when a peer lacks SPQR support, so coverage is universal at the handshake (PQXDH) and progressively universal for the ongoing ratchet (SPQR). | No Telegram does not advertise or document any post-quantum (e.g. ML-KEM) protection in MTProto as of 2026. |
| Requires a phone number | Yes A working phone number that can receive an SMS/call is still mandatory to create an account. Usernames (added 2024) only let others reach you without seeing your number; they do not replace the number for registration. | Yes Telegram's FAQ states the phone number 'is the only way for us to identify a Telegram user.' A real SIM is not strictly required — virtual numbers or paid Fragment 'anonymous numbers' work — but a number that can receive an OTP is mandatory. |
| Requires an email address | No | No |
| How you’re identified | Phone number is required to register; an optional username lets you be contacted without sharing the number | Phone number is the primary identity; a public @username can be added. Anonymous blockchain numbers via Fragment are possible but paid and not the default. |
| Architecture | centralized | centralized |
| Metadata protection | Sealed sender hides the sender from Signal's servers; private contact discovery and encrypted profiles/groups minimize what the server can see, but a central server still routes all traffic Sealed sender gives one-way sender anonymity from the server, and private contact discovery plus SGX-backed features reduce server knowledge. Government subpoenas (2016, 2021) confirmed Signal could only produce account-creation and last-connection timestamps. However, a central server still sees connection metadata such as IP and timing, which is why it is 'centralized' rather than a metadata-minimal P2P design. | no Telegram offers no sealed-sender, Tor routing, or mixnet. Following a September 2024 policy change, Telegram's Privacy Policy states it may disclose a user's IP address and phone number to authorities on a valid court order in criminal cases; its quarterly transparency channel (t.me/transparency) shows a large jump in fulfilled requests after that change. |
| Routes over Tor by default | No Signal does NOT route over Tor by default. It offers censorship circumvention (domain fronting / proxy support) when blocked, and users can manually run it through Tor/Orbot, but normal traffic goes to Signal's servers directly. | No |
| Open-source client | Yes | Partial Client apps are open source with reproducible builds, which lets users verify the app binary matches published code. However, the server software is fully closed source, so the actual handling of cloud-chat data cannot be independently inspected. |
| Independently audited | Partial Marked partial: the Signal Protocol has strong academic formal-analysis pedigree (e.g., Cohn-Gordon et al., IEEE EuroS&P 2017) and PQXDH received formal verification, but these are protocol/cryptography analyses rather than recurring full-stack commercial penetration audits of every client. Signal is exceptionally well-scrutinized for a messenger; 'partial' reflects that it is not a single, recent, end-to-end commercial audit of all apps. | Partial Marked partial: independent academic security analyses of MTProto have been published, but there is no full independent audit of Telegram's production servers and infrastructure, and the closed server makes one impossible. Treat as effectively unaudited at the system level. |
| Jurisdiction / who can be subpoenaed | United States (Signal Foundation / Signal Messenger LLC, 501(c)(3) nonprofit, California) | Operationally headquartered in Dubai (UAE); legal entity Telegram Group Inc. is incorporated in the British Virgin Islands |
| On-device duress / panic defenses | No Signal supports disappearing messages, a Signal PIN, registration lock, and screen lock, but has no built-in duress/decoy PIN or panic-wipe; a community feature request for a duress wipe was declined by Signal. | No Telegram offers a passcode lock and self-destructing Secret Chats, but no duress/decoy PIN or panic-wipe feature equivalent to a coercion defense. |
| Max attachment size | ~100 MB per attachment (varies by platform: ~100 MB Android/Desktop, smaller on iOS) Commonly cited as ~100 MB per attachment, with per-platform variation (Android/Desktop near 100 MB, iOS images notably smaller). Limits change over time; treat as approximate. | 2 GB per file (free); 4 GB with Telegram Premium |
| Collects telemetry / analytics | No Signal is funded by donations/grants, runs no ads, and does not monetize data. Subpoena responses demonstrate it does not retain message content, contacts, or profile data; it is widely regarded as not running analytics/telemetry on users. | Partial Marked partial: Telegram collects metadata (phone number, contacts you import, IP addresses, device info) and stores cloud chats on its servers, but states it does not use this data for third-party ad targeting in private chats. It is not a no-telemetry/no-metadata design. |
The verdict
For private messaging, Signal is the clearer choice: it is end-to-end encrypted by default for all chats and calls, is fully open-source and independently studied, holds almost no user data, and has already shipped post-quantum cryptography — there is no setting to forget to turn on. Telegram is genuinely excellent at what it optimizes for — speed, huge group/channel communities, bots, and large file transfers (up to 2 GB free, 4 GB with Premium) — but its default chats are not E2EE, so if confidentiality matters you must remember to start a Secret Chat for every sensitive one-on-one conversation, and you simply cannot get E2EE for groups or channels at all. If your goal is privacy, treat Telegram as a social/broadcast platform rather than a secure messenger.
Both still tie your identity to a phone number and route through central servers. If you want to go a tier further on metadata and identity minimization — no phone number, no central servers holding your content, and onion-style metadata protection — purpose-built privacy tools push harder on those fronts. RVNT takes that maximal path: fully peer-to-peer (no central server for content), end-to-end encrypted by default with post-quantum cryptography, and no phone-number identity. It's the right fit only if metadata minimization is your priority; for most people who just want messages their provider can't read, Signal already does that well.
Frequently asked questions
Is Telegram end-to-end encrypted?
Only partially. Telegram's default "cloud chats" are encrypted between your device and Telegram's servers (MTProto 2.0), but Telegram can decrypt and read them on its servers. True end-to-end encryption is available only in **Secret Chats**, which you must start manually, work only for one-on-one conversations (not groups or channels), and are tied to a single device. By contrast, every Signal chat and call is end-to-end encrypted by default.
Both Signal and Telegram need my phone number — so is the privacy difference real?
Yes. A phone number affects *identity/discovery*, but the bigger difference is *content custody*. On Signal, your messages are E2EE by default, so even though Signal knows a number registered, it cannot read your messages and has shown in court it holds almost no data. On Telegram, your default chats sit on Telegram's servers in a form Telegram can decrypt. Same registration requirement, very different exposure of what you actually say. Messengers like RVNT, Session, and SimpleX avoid the phone number entirely if that specific concern matters to you.
Comparisons here are kept honest and dated — we name where the other app wins. RVNT is the post-quantum, peer-to-peer option with no phone number and no servers.