Swiss messenger that works without a phone number
Threema is a privacy-focused messenger from Switzerland that end-to-end encrypts messages, calls, groups and files. Each user gets a random Threema ID, so no phone number or email address is required, and the address book is only synced if you choose to. The apps are open source and sold for a one-time fee, while Threema Work targets companies and public institutions.
- features
- 5
- alternatives
- 9
- platforms
- 5
- Updated
- Oct 12, 2026
Features
Our take
Pros
- No phone number or email needed, thanks to a random Threema ID
- Swiss company with a strong privacy focus and GDPR compliance
- One-time purchase instead of ads or a subscription
Cons
- Being a paid app discourages contacts from joining
- Smaller user base than mainstream messengers
Editorial assessment by the Alternatives.tools team, based on what the product is known for. Not a user review.
Best Threema alternatives
See all 9 alternatives
SignalFreeOpen sourcePrivate messaging with end-to-end encryption for everything
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SessionFreeOpen sourceAnonymous messaging over a decentralized onion-routed network
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SimpleX ChatFreeOpen sourcePrivate messenger with no user identifiers at all
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OlvidFreemiumOpen sourceFrench secure messenger with no phone number or directory
4.5(42) · App Store- WhatsAppFree
Encrypted messaging and calls tied to your phone number
4.7(18.8M) · App Store 
TelegramFreemiumOpen sourceCloud-based messaging with large groups, channels and bots
4.0(282.8K) · App Store
User reviews
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