1 Best Open-Source Alternatives to Tresorit in 2026
By Noahlast updated
Compared: open-source alternatives to Tresorit
| Alternative | Best for | Standout | Biggest weakness | Learning curve | Price |
|---|---|---|---|---|---|
| Tresoritreference | financial, legal, and healthcare teams that need zero-knowledge encrypted file storage plus encrypted data rooms for sharing with outside parties | Zero-knowledge, client-side encryption combined with Tresorit Engage's encrypted data rooms, letting compliance-sensitive teams collaborate with external clients and partners without ever exposing files to Tresorit's own servers. | No permanent free tier and no self-serve pricing transparency: exact per-user costs are not published as plain numbers on the live pricing page (they render via client-side JavaScript), and third-party sources quote inconsistent figures, so buyers have to request a quote or dig through a trial signup to confirm current cost. | Moderate | Custom pricing |
| Proton Drive | privacy-focused individuals and small teams who want end-to-end encrypted cloud storage with a genuinely usable free tier and open-source, independently-audited clients | Files are end-to-end encrypted before upload — Proton itself cannot read them — and the client source code (GPL-3.0) is public on GitHub for independent review. | End-to-end encryption means there is no way for Proton to recover a lost password or restore access to encrypted files without a saved recovery kit; the free tier's 5 GB is modest, and getting the best per-dollar value requires bundling into the pricier $12.99/month Proton Unlimited plan rather than buying Drive storage alone. | Low | Free tier · paid from $4.99/mo |
Tresorit
Proton Drive1.Proton Drive — best Tresorit alternative for privacy-focused individuals and small teams who want end-to-end encrypted cloud storage with a genuinely usable free tier and open-source, independently-audited clients
Proton Drive is the best Tresorit alternative for individuals and small teams who want end-to-end encrypted cloud storage without Tresorit's 14-day-trial-then-pay model. Proton Drive's Free plan gives 5GB of storage at no cost, and Drive Plus costs just $4.99/month for 200GB, compared to Tresorit's Professional tier, which has no published price and requires at least 1 paying user with no permanent free option. Like Tresorit, Proton Drive encrypts files on-device before upload so the vendor cannot read stored content, but Proton Drive goes further by publishing its client source code on GitHub under GPL-3.0 for independent review, something Tresorit's closed-source clients do not offer. Tresorit is still the better choice for regulated financial, legal, and healthcare teams that specifically need Tresorit Engage's encrypted data rooms for external due-diligence collaboration, SSO integration with Azure AD or Okta, and a choice of 12 global data-residency regions, none of which Proton Drive's four consumer-oriented tiers provide. Proton Drive's free tier is also more modest than some rivals at just 5GB, and a lost password with no saved recovery kit means permanently lost access to encrypted files.
Compared to Tresorit: has a permanent free tier (5GB) vs none, open-source GPL-3.0 clients vs closed-source, cheaper entry price ($4.99/mo Drive Plus vs no published Tresorit price)
Wins:Permanent free tier (5GB) vs Tresorit's 14-day-trial-then-pay model with no free option · Client source code is public on GitHub under GPL-3.0 vs Tresorit's closed-source clients · Drive Plus starts at $4.99/month for 200GB, a published, transparent price vs Tresorit's unpublished per-user figures
Loses:No Tresorit Engage equivalent for encrypted data rooms with external clients and partners · No SSO integration (Azure AD, Okta, Google) or choice of 12 global data-residency regions · Lost passwords cannot be recovered without a saved recovery kit, and the free tier's 5GB is modest next to some rivals
Pros
- Files are end-to-end encrypted client-side, so Proton cannot read stored content.
- Client source code is open source (GPL-3.0) and independently audited.
- 5 GB free tier is more generous than most end-to-end encrypted competitors.
- Based in Switzerland, subject to strict Swiss privacy law rather than US or EU data requests.
Cons
- Lost passwords can't be recovered by Proton for end-to-end encrypted content without a saved recovery kit.
- Free tier storage (5 GB) is modest compared to Google Drive's 15 GB free tier.
- Best value per dollar requires the pricier Proton Unlimited bundle rather than a Drive-only plan.
Pricing: Free tier · paid from $4.99/mo — $4.99/month Drive Plus (200GB) vs Tresorit's unpublished Professional pricing (Tresorit shows no plain-text dollar figures on its live pricing page) (verified undefined NaN, NaN)