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Encrypted Messaging for UK Journalists

Signal is the gold standard for journalist-source communications. But knowing why — and knowing when Signal is not enough — matters as much as the tool itself.

General guidance, not professional security advice. For high-risk threat models involving state actors or organised crime targeting, consult a qualified security professional or the Access Now Digital Security Helpline.

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Why encrypted messaging matters for journalists

Standard SMS and unencrypted email are not confidential. Your mobile operator can read SMS messages; your email provider can read your emails; and both can be compelled to produce records by court order or by law enforcement requests under the Investigatory Powers Act 2016. For most journalism this is fine — but for any communication involving a confidential source, an unencrypted channel creates an evidence trail that can expose the source.

End-to-end encrypted (E2E) messaging solves this by encrypting messages on the sender’s device, so that only the recipient can decrypt them. The service provider never sees the message content. The practical caveat: encryption protects messages in transit. Once a message arrives on a device, it is only as secure as that device.

Tool comparison

SignalGold standard

Open-source, audited Signal Protocol. Minimal metadata collection. Disappearing messages. Phone number required (use a separate SIM for high-risk work). Best for journalist-source messaging and calls.

ProtonMailBest for email

Swiss-based, zero-access encryption for stored emails. E2E encrypted between ProtonMail users; standard encryption to non-ProtonMail addresses. Good for initial contact from unknown sources.

TutanotaSolid alternative

German-based encrypted email with calendar. E2E between Tutanota users; password-protected for external recipients. Open-source clients. Very similar to ProtonMail in practice.

WireFor teams

E2E encrypted messaging and calls, designed for teams. Allows username login without a phone number. Useful for newsroom-wide secure communications. Audited. Less popular than Signal for individual source contact.

WhatsAppLow-risk only

E2E encrypted message content (Signal Protocol). However, Meta collects significant metadata. Backup to iCloud/Google Drive may not be E2E encrypted by default. Acceptable for low-sensitivity conversations; not for sensitive sources.

SMS / iMessage (green bubbles)Avoid for sources

Standard SMS has no encryption. iMessage is E2E encrypted between Apple devices but backups to iCloud may expose messages. SMS records can be subpoenaed from mobile operators. Do not use for source communications.

Red flags

  • Communicating with a sensitive source via standard SMS or unencrypted email.
  • Using your work email account (hosted by a third party) for source communications.
  • WhatsApp backups enabled on iCloud or Google Drive without additional encryption.
  • Not using disappearing messages for sensitive source conversations.
  • Using Telegram (not E2E by default — only "Secret Chats" are encrypted) as if it were Signal.
  • Sharing source information over Slack or Microsoft Teams (not E2E encrypted, employer can read).

Encrypted messaging checklist

  • I have Signal installed and have shared my Signal number with my most sensitive sources.
  • I have enabled disappearing messages (set to a time appropriate to the sensitivity of the story).
  • I have a ProtonMail or Tutanota address I can share publicly for initial source contact.
  • I have confirmed that sources know not to contact me via standard SMS or plain email for sensitive matters.
  • I have reviewed whether my WhatsApp backups are encrypted end-to-end (WhatsApp settings > Chats > Chat backup > End-to-end encrypted backup).
  • I have not discussed unpublished source identities over Slack, Teams, or work email.
  • For very high-risk sources: I have directed them to the newsroom's SecureDrop or OnionShare address instead.

Source protection tools

Use our source protection checklist to assess whether your communication setup is adequate.

Source Protection Checklist

Common mistakes

  • Treating Telegram as equivalent to Signal — Telegram chats are not E2E encrypted by default.
  • Ignoring metadata: even Signal reveals who you contacted and when to a network observer.
  • Using the same phone number for Signal that is linked to your professional identity.
  • Forgetting that cloud backups (iCloud, Google) may contain unencrypted message copies.
  • Not briefing sources on how to use Signal before they need it urgently.

Related guides

Secure File Sharing
SecureDrop, OnionShare, and transferring sensitive documents safely.
Threat Modelling
Assess your threat level before choosing your communications tools.
Device Security
Protecting the device that holds your encrypted messages.
Metadata & Document Cleaning
Stripping identifying metadata from documents before sharing.

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Frequently asked questions

Is Signal really end-to-end encrypted?
Yes. Signal uses the Signal Protocol, which is open-source and independently audited. Messages are encrypted on your device and can only be decrypted by the recipient's device. Signal itself cannot read your messages. However, the encryption only covers content in transit — if your phone is seized and unlocked, Signal messages can be read directly from the app.
Why is WhatsApp not good enough for sensitive sources?
WhatsApp uses the Signal Protocol for message encryption, so message content is E2E encrypted. The problem is metadata: WhatsApp collects and shares with Meta a significant amount of metadata — who you contacted, when, how often, and from which location. This metadata alone can reveal a source. For low-risk conversations, WhatsApp is fine. For sensitive sources, use Signal, which collects the bare minimum metadata.
Should I use a secure email provider or just Signal?
For initial contact with unknown sources, encrypted email (ProtonMail or Tutanota) is useful because sources can reach you without installing an app. However, email — even encrypted — involves more metadata than Signal and is slower. Once contact is established, move the conversation to Signal if the source's threat model allows. For very high-risk sources, use SecureDrop over Tor instead.
What is disappearing messages and should I use it?
Disappearing messages automatically delete after a set time — Signal, WhatsApp, and Telegram all offer this. For journalists, it is a double-edged feature: it protects sources but can also destroy evidence you need to keep for legal defence or to demonstrate right-of-reply compliance. Use disappearing messages for source contact; retain your own notes and editorial documentation separately in a secure location.

Related guides

Digital SecuritySecure File Sharing: SecureDrop & OnionShareRead →Digital SecurityDevice Security for UK JournalistsRead →InvestigativeProtecting Sources in Investigative JournalismRead →Media LawLegal Source Protection in the UKRead →SafetyJournalist Wellbeing Under PressureRead →

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