Signal vs Telegram: The Default-Encryption Gap That Most Reviews Miss
Telegram markets itself as "secure" and "encrypted," but its regular chats and group chats are not end-to-end encrypted. Only opt-in "Secret Chats" are. Signal encrypts every chat, call, and group by default. This page compares the two messengers purely on security: default E2EE, metadata, source openness, audits, and government data exposure.
Security comparison: 13 dimensions
| Dimension | Signal | Telegram |
|---|---|---|
| Default end-to-end encryption | ★ Every chat, call, group, status — always on, not opt-in | NO — only Secret Chats (opt-in, 1:1 only). All other chats are client-server / MTProto transport encryption |
| Encryption protocol | Signal Protocol — designed and maintained by Signal Foundation; free licence to others | MTProto (Telegram's custom protocol); audited but closed |
| Metadata collection | ★ Minimal — sealed sender hides who is messaging whom; only phone + last connection date stored | Significant — phone number, contacts, username, profile, last seen, online status, group memberships, channel subscriptions |
| Cloud backups (E2EE?) | ★ No cloud backups — Signal deliberately does not back up messages anywhere | Cloud chats are stored on Telegram servers (NOT E2EE); Secret Chats never sync to cloud |
| Open-source clients | Yes — fully open (GitHub) | Yes — open source clients |
| Open-source server | ★ Yes — Signal Server on GitHub | No — server is closed |
| Independent audits | ★ Multiple, ongoing, public | Limited — only MTProto audited; server never audited |
| Group chat E2EE | ★ Always on (all sizes) | Group chats are NOT E2EE (server can read) |
| Phone number as identity | Yes (since 2024 optional username, but account still bound to real number) | Yes — phone number is the identity |
| Multi-device | Up to 5 linked devices — E2EE preserved, primary phone is source of truth | Unlimited — full cloud sync across all devices (this is the explicit design choice) |
| Government data requests | ★ Publishes transparency reports; in recent 12 months ~2,230 subpoenas, mostly for "registration date" only | Publishes transparency reports; has disclosed user data in terrorism cases per policy |
| Business model & incentives | Nonprofit — donations only | For-profit (premium subscriptions); Pavel Durov personally controls |
| Approx. monthly active users | ~70 million | ★ ~950 million |
★ marks the dimension where one app clearly wins on security.
Sources: Signal official docs,
Telegram MTProto / E2EE docs,
Signal Transparency Reports (2024), Telegram Transparency Reports (2024).
Who should pick which (on security grounds)
Choose Signal if security is your priority
- You want every chat encrypted by default — not "encrypted if I remember to enable it"
- You care about group chat encryption — Telegram's 200K-member groups are NOT E2EE
- You don't trust Telegram's "we won't give data to governments" promise without audit
- You want full open-source transparency (Signal server is on GitHub; Telegram's is not)
- You're a journalist, activist, lawyer, doctor — any threat model where default-encryption matters
Choose Telegram if reach and features matter more
- You want 200K-member groups, channels for broadcasting, bots — Telegram is unmatched here
- You're OK with enabling Secret Chat manually for sensitive conversations
- You live in a region where Telegram is the de-facto messenger (Eastern Europe, parts of Asia, Middle East)
- You want full unlimited cloud sync — Telegram is genuinely the best in this category
- You don't need group chat encryption (mostly use 1:1 in Secret Chat mode anyway)
The default-E2EE gap that most reviews miss
Telegram's marketing page says "heavily encrypted." Its CEO has publicly claimed "Telegram is more secure than Signal." Both statements are misleading. What matters is what Telegram calls "client-server / server-client encryption": your messages are encrypted in transit between your device and Telegram's servers, and Telegram's servers can decrypt them because they hold the keys. That is not end-to-end encryption.
Telegram does offer end-to-end encryption — but only in opt-in "Secret Chats" that: (1) must be manually initiated per contact, (2) work only on the device you start them on (no cloud sync), (3) are not available for group chats at all. The vast majority of Telegram traffic — regular chats, group chats, channels — flows through Telegram's servers in a form Telegram itself can read.
Why Telegram chose this design (and why it matters)
Telegram's CEO Pavel Durov has explained the design choice: end-to-end encryption "kills" the user experience because encrypted data can't be backed up, indexed, or synced across devices. That's true, but it's a trade-off that erases the security guarantee most users think they're getting.
The result: a user who opens Telegram, chats with friends, and joins group chats is operating under the assumption that their messages are private. They are not, by Telegram's own design. If Telegram's servers are breached, compelled by a government, or simply abused by an insider, every non-Secret Chat is exposed.
What "Signal Protocol" actually is — and why Telegram doesn't use it
Signal uses the Signal Protocol (Double Ratchet + X3DH), designed by Moxie Marlinspike and Trevor Perrin, currently maintained by Signal Foundation. It's the same protocol WhatsApp, Google Messages, and Skype use under licence. It is the most peer-reviewed messaging cryptography in the world, with a dozen published academic analyses.
Telegram uses MTProto, a protocol Telegram designed in-house. MTProto has been audited (the encryption itself is fine), but the fact that Telegram had to invent its own cryptography stack rather than using the field-standard Signal Protocol is itself a yellow flag. Most security researchers recommend using battle-tested protocols rather than novel ones.
Metadata: Telegram is closer to WhatsApp than to Signal
Telegram collects substantial metadata: your phone number, contacts, username, profile, last-seen timestamp, online status, every group you've joined, every channel you follow. This metadata profile is similar in scope to WhatsApp's — and far more exposed than Signal's "sealed sender" design, where Telegram's equivalent (Signal's servers) cannot tell who is messaging whom.
Open source: clients yes, server no
Telegram's iOS, Android, and desktop clients are open source on GitHub. Signal's clients and server are open source. The difference: when a security researcher audits Signal, they can read the server code that handles your data. When they audit Telegram, they cannot — the server code has never been published. That's a non-trivial transparency gap.
Group chats: where the gap is largest
Telegram's headline feature is 200,000-member groups and unlimited channels. None of these are end-to-end encrypted. A journalist creating a "sources wanted" group on Telegram is broadcasting every message through Telegram's servers. The same journalist creating a Signal group of 1,000 people is fully E2EE-protected. This is not a minor trade-off — for high-risk use cases, the choice is categorical.
What Telegram is actually best for
None of this means Telegram is bad. It means Telegram is best for the things it's optimized for: large groups, channels, broadcasting, bots, file sharing, and unlimited cloud sync. If those are your priorities and you remember to use Secret Chat for sensitive 1:1 conversations, Telegram is a fine choice. If your threat model includes "I want every message to be encrypted by default and I don't want to remember to enable it," Signal is the answer.
Reddit consensus (r/privacy, r/signal, r/Telegram)
The recurring r/privacy advice: "Signal for private messages, Telegram for everything else." The technical consensus is that Signal is materially more secure on every dimension that matters (default E2EE, metadata minimization, source openness, audits). The disagreement is about UX trade-offs and ecosystem.
r/Telegram tends to push back on the framing, arguing that E2EE-by-default is overkill for most users, that Telegram's server-side encryption is "good enough," and that the auditability of MTProto plus the no-data-sharing-to-third-parties policy is acceptable. Both perspectives have merit; the right answer depends on your threat model.
Verdict
On pure security, Signal wins on seven of the thirteen dimensions above, including the most important one (default E2EE). Telegram wins on user base and feature set. If you want security-by-default, choose Signal. If you want a feature-rich messenger and will manually use Secret Chat for sensitive conversations, Telegram is fine.