Business email and office suites · Comparison
Fastmail for Business vs Proton for Business
2 products compared side by side: what you pay for with each one first, then the five access facts, entry prices, recorded plan limits and the bottom line of each review. The evidence note under the table says how each product was checked.
Side by side
| Metric | Fastmail for Business | Proton for Business |
|---|---|---|
| What you're paying for | Worth the priceEmail, calendars and contacts on your own domain with 60 GB per user for $5 a month on 12-month terms, with open protocols and a documented API. | Compliance includedEnd-to-end encrypted email and calendar on your own domain, with 1 TB per user, Docs, Sheets and recorded meetings on Workspace Standard. |
| Overall score | 5.7 | 6.4Best |
| Free option | 30-day free trial | 14-day free trial |
| Card to start | No card needed | –Not measured |
| Getting access | Self-serve | Self-serve |
| Starter priceCheapest paid plan | $3/user/mo | $6.99/user/mo |
| Pricing model | Per seat | Per seat |
| Pricing page | Public prices | Public prices |
| Billing unit | Per user per month; cheaper on 12-, 24- and 36-month terms | Per user per month; storage pooled across Mail and Drive |
| Free option | No free plan; 30-day trial for 5 active users, no card | No free plan on a custom domain; 14-day trial for up to 10 users, payment method needed; 30-day money-back guarantee |
| Reference scenario (5 users, annual) | $25/mo on Standard ($5 × 5), computed | $64.95/mo on Workspace Standard ($12.99 × 5), computed |
| Month-to-month price | $6 per user on Standard ($4 / $10 for Basic / Professional) | $14.99 per user on Workspace Standard ($7.99 / $24.99 for Essentials / Premium) |
| Storage per user | 6 GB (Basic), 60 GB (Standard), 150 GB (Professional), per user | 15 GB (Mail Essentials), 1 TB (Workspace Standard), 3 TB (Premium), pooled |
| Domains, aliases and catch-all | From Standard: 100 domains plus 1 per user, 600 aliases plus 15 per user, catch-all | 3, 15 or 20 domains (extra $1.40/mo on Workspace); 10 or 20 addresses per user; catch-all |
| Office apps | None; file storage with WebDAV | Proton Docs and Sheets in the browser on every plan |
| Video meetings | Not offered | Proton Meet for 100 for 24 hours with local recording on Workspace Standard |
| Retention and eDiscovery | Retention archive on Professional ($9); no eDiscovery | Retention policies on Workspace Premium; no eDiscovery |
| SOC 2 / ISO 27001 | No SOC 2 certification pursued; ISO 27001 not stated | SOC 2 Type II (report on request) and ISO 27001 |
| HIPAA BAA | Not offered (not HIPAA compliant) | Offered to all users, signed on request by email |
| EU data storage | EU or US primary storage on every plan; replica, backups and logs in the US | Swiss jurisdiction; no region choice stated |
| SAML SSO | Not offered | Not supported for Proton Mail yet |
| Mailbox export | ZIP per folder for each user (format not stated); no admin export of all users | Per user with the Export Tool (EML and JSON); no admin export of all mailboxes |
| Bottom line | From its public pages, Fastmail is a focused email, calendar and contacts service with 60 GB per user for $5, open protocols and no lock-in. It has no office suite, meetings, SSO or SOC 2 report, and its help articles disagree on a few limits and deletion periods. | From its public pages, Proton for Business is the encryption-first option here, with audits, a BAA on request and a 30-day guarantee. The scenario needs Workspace Standard at $64.95 for five, and SSO, admin-wide export and a mail API are not offered. |
Evidence: Fastmail for Business: facts checked 2026-10-16 from its public sign-up and pricing pages, no completed hands-on run; Proton for Business: facts checked 2026-10-16 from its public sign-up and pricing pages, no completed hands-on run. Prices in USD as listed, excluding tax. "–" means not recorded.
When to pick each
In the words of each review, with the date its facts were checked.
From our Fastmail for Business review
Checked Oct 16, 2026- Pick Fastmail for Business when
- You want IMAP without a bridge app, a JMAP API, EU or US data residency and $25 a month for five.
- Pick Proton for Business when
- You need end-to-end encryption, SOC 2 Type II, ISO 27001, a BAA, or Docs, Sheets and meetings.
From our Proton for Business review
Checked Oct 16, 2026- Pick Proton for Business when
- You need end-to-end encryption, SOC 2 Type II and ISO 27001, a BAA, or Docs, Sheets and meetings.
- Pick Fastmail for Business when
- You want IMAP without a bridge app, a JMAP API and a lower price ($25 a month for five on Standard).
Entry price
Baseline: each product's cheapest paid plan, per month. Included usage differs, so read the line under each price.
- Fastmail for BusinessBasic$3/user/mo12-month terms; $4 month to month; $2.80 on 36 months
- 6 GB per user (5 GB of mail, 1 GB of files)
- Own-domain addresses only with a Standard or Professional admin
- Web and mobile apps only: no IMAP, POP or API tokens
- Proton for BusinessMail Essentials$6.99/user/moBilled annually; $7.99 month to month; $6.49 on 24 months
- 15 GB per user, pooled across Mail and Drive
- 3 custom domains, 10 addresses per user, catch-all
- Proton Docs and Sheets
- Meet for 50 for up to 1 hour
Prices as listed on each pricing page, in USD per month, excluding tax. Observed: Fastmail for Business 2026-10-16, Proton for Business 2026-10-16.
Which one fits
- If you need to start today without a sales call
- Proton for BusinessSelf-serve sign-up; the highest score of the 2 self-serve products here (6.4/10).
- If you want to try it without entering a card
- Fastmail for Business30-day free trial, no card needed; scored 5.7/10.
- Lowest starter price
- Fastmail for Business$3/user/mo for the Basic (12-month terms; no own domain) plan.
- Highest overall score
- Proton for Business6.4/10 (Good). The review shows the score breakdown and the run behind it.
Picked by fixed rules from the table above, not by hand. How we score
Full reviews
More in Business email and office suites
Add a product
Search by product name or by what it does, such as “email” or “feature flags”. 2 more fit in this comparison.