Proton Mail vs Fastmail for Business
Proton Mail wins on privacy, Proton Mail wins on price and Fastmail for Business wins on features. Every fact below was checked on or before 23 October 2026.
Proton Mail or Fastmail for Business: which should you choose?
- Proton Mail is the better pick if you want encryption that means even the provider can't read your mail; to pay less: $3.99 a month, yearly ($4.99 monthly); and a free plan to start on.
- Fastmail for Business is the better pick if you want 50 GB of storage; freedom to use the mail app you already like; and extras such as POP3 as well as CalDAV and CardDAV sync.
| Feature | Proton Mail | Fastmail for Business |
|---|---|---|
| Overall | 4.5 | 3.0 |
| Privacy | 5.0 | 2.0 |
| Price | 4.0 | 3.5 |
| Features | 4.5 | 5.0 |
| Cheapest plan | Mail Plus $3.99 a month, yearly ($4.99 monthly) | Standard $5 per user a month ($4.17 yearly) |
| Free plan | Yes, 1 GB, no own domain | No |
| Storage | 15 GB | 50 GB |
| Your own domain | ✓ 1 | ✓ 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 | Free plan; 30-day refund on paid plans | 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 | 10 addresses | Yes |
| Open-source apps | ✓ Yes | No |
| Sign up without ID | ✓ Yes | No |
| White label | No | No |
| Reader offer | Offer Proton's current deals | Offer 10% off your first year, plus a free trial of up to 30 days |
| Last checked | 23 October 2026 | 22 October 2026 |
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How Proton Mail and Fastmail for Business differ
- Proton Mail's cheapest plan is Mail Plus ($3.99 a month, yearly ($4.99 monthly)); Fastmail for Business's is Standard ($5 per user a month ($4.17 yearly)).
- For free, Proton Mail gives you a free plan (1 GB, no own domain), and Fastmail for Business no free plan.
- Proton Mail comes with 15 GB of storage and Fastmail for Business with 50 GB of storage.
- Proton Mail keeps your mail in Switzerland, while Fastmail for Business keeps it in the EU (Amsterdam) for UK customers, with a US replica and US backups.
- Proton Mail is based in Switzerland and Fastmail for Business in Australia, so different privacy laws apply.
- Proton Mail encrypts mail end to end; Fastmail for Business doesn't encrypt mail end to end.
- Proton Mail works in other mail apps through Proton Bridge on paid plans, and Fastmail for Business works in any mail app over IMAP.
- For extra addresses, Proton Mail has 10 addresses and Fastmail for Business has yes.
Proton Mail and Fastmail for Business: your questions
Which is more private, Proton Mail or Fastmail for Business?
Proton Mail scores 5 out of 5 for privacy and Fastmail for Business 2. Proton Mail gives you encryption that means even the provider can't read your mail, apps whose code is public and to sign up without proving who you are.
Which is cheaper, Proton Mail or Fastmail for Business?
Proton Mail is cheaper. Its Mail Plus plan is $3.99 a month, yearly ($4.99 monthly), against $5 per user a month ($4.17 yearly) for Fastmail for Business's Standard. Proton Mail also has a free plan. Check the renewal price before you pay, as some first-year prices go up.
Do Proton Mail and Fastmail for Business work with my own domain?
Yes, both do. Proton Mail: 1 domain on its cheapest plan that allows one. Fastmail for Business: Up to 100.
Where do Proton Mail and Fastmail for Business keep my email?
Proton Mail keeps it in Switzerland. Fastmail for Business keeps it in the EU (Amsterdam) for UK customers, with a US replica and US backups.
Do Proton Mail and Fastmail for Business work in other mail apps?
Proton Mail 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
No price changes for either since 22 October 2026. I check regularly and add any change here with its date.
The latest headlines: Proton Mail news · Fastmail for Business news.
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Switching between them
Moving to Proton Mail · Moving from Proton Mail. Or see all my switching guides.