Updated September 28, 2026 · ShieldCue Editorial Team
SimpleX Chat vs Threema
What sets them apart
| Compare |  SimpleX Chat |  Threema |
|---|---|---|
| Free plan limits | Free | Unlimited messages, free updates for all platforms, max. 200 users; private app is a one-time 6.00 purchase |
| Platforms | Android, iOS, Windows, MacOS, Linux, Terminal CLI | Android, iOS, Windows, Macos, Linux, Web |
| Logging policy | Preset servers do not log IP addresses of the user devices that connect to them; messages are irreversibly removed from preset relay servers as soon as delivered or after 21 days; files kept 48 hours on preset file servers; only aggregate statistics collected. | Metadata restraint: messages deleted from servers immediately after delivery, connection information not logged, group memberships kept only on devices |
| Jurisdiction | GB | CH |
| Price from | Not confirmed | CHF 3 |
Same on both: Free plan (Yes), Open source (Yes).
We earn a commission when you sign up through links on this site. Partner status can affect where a brand appears in our rankings.
Key differences
- Platforms: only SimpleX Chat offers Terminal CLI.
- Platforms: only Threema offers Web.
- Support channels: only SimpleX Chat offers Chat.
- Founded is lower at Threema: 2012 vs 2021.
- Pricing model: only Threema offers Budget.
Our verdict on each
SimpleX Chat
SimpleX Chat is a free, open source messenger where messages, files and calls stay end-to-end encrypted, so it suits people who want private chat without a subscription. It runs on Android, iOS and Windows, was founded in 2021, and the Free plan costs nothing at entry or at renewal.
Threema
Threema suits readers who want encrypted messaging on their own terms, with a free plan that covers unlimited messages. The paid app is a single purchase rather than a renewal, entry price of CHF 3 keeps the paid tier modest, the apps are open source, and support runs on email, help centre and community.
Score breakdown
| Area | SimpleX Chat | Threema |
|---|---|---|
| Cost | 9.1 | 9.3HigherEntry price CHF 3 ranks 28 of 131 brands, under the site median of €6.84. |
| Offer | 9.5Higher | 9.1 |
| Privacy | 8.7 | 9.2Higher |
Positions in our rankings
| Ranking | SimpleX Chat | Threema |
|---|---|---|
| Privacy tools | 92 of 280 | 93 of 280 |
| Secure email and messaging | 22 of 60 | 23 of 60 |
Pick SimpleX Chat if, pick Threema if
Pick SimpleX Chat if offer matter most.
Pick Threema if privacy matter most.
What we checked
SimpleX Chat
- simplex.chat: 9 facts, checked September 26, 2026
- f-droid.org: 1 fact, checked September 26, 2026
- find-and-update.company-information.service.gov.uk: 1 fact, checked September 26, 2026
Threema
- threema.com: 11 facts, checked September 26, 2026
- en.wikipedia.org: 1 fact, checked September 26, 2026
Every fact side by side
| Fact | SimpleX Chat | Threema |
|---|---|---|
| Pricing model | Free | Free, BudgetCovers more |
| Legal entity | SimpleX Chat Ltd | Threema AG |
| Headquarters | United Kingdom | Switzerland |
| Founded | 2021 | 2012Lower |
| Support channels | Email, Chat, Help centre, CommunityCovers more | Email, Help centre, Community |
Secure email
| Fact | SimpleX Chat | Threema |
|---|---|---|
| End-to-end encryption | Messages, files and voice messages, plus audio and video calls, are end-to-end encrypted; relay servers cannot decrypt content | All messages, voice and video calls including group calls, and shared files, encrypted end to end between the participants; Threema itself cannot read the content |
Pros and cons
SimpleX Chat
Pros
- Messages, files, voice messages, audio and video calls are all end-to-end encrypted, and relay servers cannot decrypt the content
- It is open source and free, listed under free, with a Free plan in place
- It covers Android, iOS and Windows, so the same account works across phone and desktop
Cons
- Support runs on email, chat and help centre only, and a phone line is not among those channels
- The Free plan limits read free, so what the free tier covers is worth checking before you lean on it for large file sharing
Threema
Pros
- End to end encryption covers messages, voice and video calls, group calls and shared files, and Threema itself cannot read the content.
- Metadata restraint: messages come off the servers as soon as they are delivered, connection information is not logged, and group memberships stay on the devices.
- A free plan with unlimited messages and free updates on all platforms, so everyday chat costs nothing to keep running.
Cons
- The free plan's cap on users means a larger group has to move elsewhere, even though the message allowance stays unlimited.
- Support runs on email, help centre and community only, with no live chat or phone line in the list.
- Against Apple Hide My Email at $0.99, Threema's CHF 3 buys a whole messenger, so the price reads high next to a single purpose tool.
Who each suits
SimpleX Chat
Who it suits
- People who want private messages, files and calls without paying a subscription
- People comfortable reading open source code and checking how a messenger handles their data
- Readers who would rather work through a help centre and community answers than ring a support line
Who should look elsewhere
- EasyOptOuts, if your goal is data broker removal rather than a private messenger: EasyOptOuts has no free plan
- Posteo, if you want a private mailbox rather than messaging: Posteo has no free plan
- Surfshark, if you would rather pay for a subscription service: Surfshark has no free plan, so there is no free open source plan to set it beside
Threema
Who it suits
- Readers who want voice and video calls inside the same encrypted app as their messages.
- People who want a free tier for everyday chat and will pay only for the extra private app.
- Teams that want a named company, open source clients and metadata restraint to point to.
Who should look elsewhere
- Readers who only want a relayed email address: Apple Hide My Email lists $0.99.
- Readers chasing the highest-priced option here, since EasyOptOuts lists $19.99.
- Readers who need live chat or a phone line, because support runs on email, help centre and community.
Current offers
Threema
Current offer
Free trial
Test Now for Free - Threema Work: 30 days with 30 users
no payment details required, no automatic renewal
Source, checked September 26, 2026
Questions about each
SimpleX Chat
How much does SimpleX Chat cost?+
SimpleX Chat lists a Free plan, and free reads free, so there is no entry price and no renewal price to weigh against each other. The Free plan's limits are free. For a messenger built on end-to-end encryption, that makes it an easy first step before you decide anything.
Is everything really end-to-end encrypted?+
Yes. Messages, files and voice messages are end-to-end encrypted, and so are audio and video calls, with relay servers unable to decrypt the content. That covers the whole conversation rather than just the text, and the app is free under free on Android, iOS and Windows.
Threema
What does Threema cost to get going?+
Threema has a free plan with unlimited messages and free updates on all platforms, so a reader can start without paying. The paid plan, the private app, starts at CHF 3 and is a single payment rather than a subscription, so there is no renewal figure to budget for later.
Can Threema read my messages?+
Messages, voice and video calls, group calls and shared files are all encrypted end to end between the participants, and Threema itself cannot read the content. Group memberships are kept only on the devices, so the company holds no readable copy of a conversation. Calls are covered by the same arrangement as typing.