Proton Mail for Business vs Stalwart
In short: Proton Mail for Business wins on privacy, Proton Mail for Business wins on price, and Proton Mail for Business wins on features. The full comparison is below, last checked 25 October 2026.
Which should you choose?
- Proton Mail for Business is the better pick if you want encryption that means even the provider can't read your mail; your mailbox stored in Switzerland; and a provider that's been going since 2014.
- Go for Stalwart if you'd like a free plan to start on and to read your mail in any app, such as Apple Mail, Outlook or Thunderbird.
| Feature | Proton Mail for Business | Stalwart |
|---|---|---|
| Overall | 4.0 | Not rated |
| Privacy | 4.5 | Not rated |
| Price | 2.5 | Not rated |
| Features | 4.5 | Not rated |
| Cheapest plan | Mail Essentials $6.99 per user a month | Community Free (Enterprise from €2 per mailbox a year) |
| Free plan | No | Yes, open source |
| Storage | 15 GB | Not confirmed |
| Your own domain | ✓ 3 | ✓ Yes |
| End-to-end encryption | ✓ Built in | No |
| Company based in | Switzerland | United Kingdom |
| Your data is kept in | Switzerland | Your own server |
| Founded | 2014 | 2019 |
| Free trial | 30-day refund | Free to download |
| Funded by advertising | No | No |
| Works in any mail app | With Proton Bridge on paid plans | ✓ IMAP and SMTP |
| Calendar and contacts | ✓ Yes | ✓ Yes |
| Aliases | Yes | Yes |
| Open-source apps | ✓ Yes | ✓ Yes |
| Sign up without ID | No | No |
| White label | No | Unknown |
| Reader offer | None | None |
| Last checked | 22 October 2026 | 25 October 2026 |
Want to add another? Open this in the compare tool.
How Proton Mail for Business and Stalwart differ
- Cheapest plans: Proton Mail for Business Mail Essentials, $6.99 per user a month. Stalwart Community, Free (Enterprise from €2 per mailbox a year).
- Proton Mail for Business has no free plan; Stalwart has a free plan (open source).
- Space: Proton Mail for Business gives 15 GB of storage, Stalwart storage not confirmed.
- Your mail is stored in Switzerland with Proton Mail for Business, and in Your own server with Stalwart.
- The companies sit under different laws: Proton Mail for Business in Switzerland, Stalwart in United Kingdom.
- On encryption, Proton Mail for Business encrypts mail end to end, whereas Stalwart doesn't encrypt mail end to end.
- Mail apps: Proton Mail for Business works in other mail apps through Proton Bridge on paid plans; Stalwart works in any mail app over IMAP.
Common questions
Can I use my own domain with Proton Mail for Business or Stalwart?
Yes, both do. Proton Mail for Business: 3 domains on its cheapest plan that allows one. Stalwart: Yes.
Where is my email stored with Proton Mail for Business and Stalwart?
Proton Mail for Business keeps it in Switzerland. Stalwart keeps it in Your own server.
Can I use Proton Mail for Business and Stalwart in Apple Mail or Outlook?
Proton Mail for Business works in other mail apps through Proton Bridge on paid plans. Stalwart works in any mail app over IMAP.
Recent price changes
I haven't seen either change its price since I started checking on 22 October 2026.
The latest headlines: Proton Mail for Business news · Stalwart news.
Also worth a look
Proton Mail for Business vs mailbox.org · Stalwart vs mailbox.org · Proton Mail for Business vs Posteo · Stalwart vs Posteo · Proton Mail for Business vs Proton Mail · Stalwart vs Proton Mail
How to switch
Moving between any two providers works the same way. Pick your two providers for the steps.