Proton Mail for Business vs Fastmail for Business
On privacy it's Proton Mail for Business. On price it's Fastmail for Business. On features it's Fastmail for Business. Here's everything side by side, last checked 22 October 2026.
Which should you choose?
- Proton Mail for Business is the better pick if you want mail that's encrypted end to end without any setup; extras such as PGP encryption as well as password-protected email to anyone; and open-source apps.
- Choose Fastmail for Business if you want to pay less: $5 per user a month ($4.17 yearly); more room (50 GB, against 15 GB); and freedom to use the mail app you already like.
| Feature | Proton Mail for Business | Fastmail for Business |
|---|---|---|
| Overall | 4.0 | 3.0 |
| Privacy | 4.5 | 2.0 |
| Price | 2.5 | 3.5 |
| Features | 4.5 | 5.0 |
| Cheapest plan | Mail Essentials $6.99 per user a month | Standard $5 per user a month ($4.17 yearly) |
| Free plan | No | No |
| Storage | 15 GB | 50 GB |
| Your own domain | ✓ 3 | ✓ Up to 100 |
| End-to-end encryption | ✓ Built in | No |
| Company based in | Switzerland | Australia |
| Your data is kept in | Switzerland | EU (Amsterdam) for UK customers, with a US replica and US backups |
| Founded | 2014 | 1999 |
| Free trial | 30-day refund | 30 days free |
| 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 | No |
| Sign up without ID | No | No |
| White label | No | No |
| Reader offer | None | Offer 10% off your first year, plus a free trial of up to 30 days |
| Last checked | 22 October 2026 | 22 October 2026 |
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Where they differ
- On price: Proton Mail for Business Mail Essentials at $6.99 per user a month, against Fastmail for Business Standard at $5 per user a month ($4.17 yearly).
- Space: Proton Mail for Business gives 15 GB of storage, Fastmail for Business 50 GB of storage.
- Your mail is stored in Switzerland with Proton Mail for Business, and in the EU (Amsterdam) for UK customers, with a US replica and US backups with Fastmail for Business.
- The companies sit under different laws: Proton Mail for Business in Switzerland, Fastmail for Business in Australia.
- On encryption, Proton Mail for Business encrypts mail end to end, whereas Fastmail for Business doesn't encrypt mail end to end.
- Mail apps: Proton Mail for Business works in other mail apps through Proton Bridge on paid plans; Fastmail for Business works in any mail app over IMAP.
Common questions
Is Proton Mail for Business more private than Fastmail for Business?
Proton Mail for Business scores 4.5 out of 5 for privacy and Fastmail for Business 2. Proton Mail for Business gives you mail that's encrypted end to end without any setup and open-source apps.
Is Proton Mail for Business cheaper than Fastmail for Business?
Fastmail for Business is cheaper. Its Standard plan is $5 per user a month ($4.17 yearly), against $6.99 per user a month for Proton Mail for Business's Mail Essentials. Check the renewal price before you pay, as some first-year prices go up.
Can I use my own domain with Proton Mail for Business or Fastmail for Business?
Yes, both do. Proton Mail for Business: 3 domains on its cheapest plan that allows one. Fastmail for Business: Up to 100.
Where is my email stored with Proton Mail for Business and Fastmail for Business?
Proton Mail for Business keeps it in Switzerland. Fastmail for Business keeps it in the EU (Amsterdam) for UK customers, with a US replica and US backups.
Can I use Proton Mail for Business and Fastmail for Business in Apple Mail or Outlook?
Proton Mail for Business works in other mail apps through Proton Bridge on paid plans. Fastmail for Business works in any mail app over IMAP.
Price changes and news
I haven't seen either change its price since I started checking on 22 October 2026.
The latest headlines: Proton Mail for Business news · Fastmail for Business news.
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