Tresorit is the enterprise zero-knowledge end-to-end-encrypted cloud-storage product operated by Tresorit AG at Pfingstweidstrasse 60b, 8005 Zurich, Switzerland (CHE-349.825.210), with offices also in Budapest, Hungary and Munich, Germany. Founded in 2011 by Hungarian engineers István Lám and Szilveszter Szebeni, the company built its reputation around mathematically-provable client-side encryption: every file, file name, and metadata is encrypted on the user device before upload, so neither Tresorit nor any data-centre operator can access plaintext customer content. The company serves 11,000+ organisations with 4.9 / 4.5 G2 / Capterra ratings.
For an EU-sovereignty audit Tresorit's ownership story is unusually strong. In July 2021 Swiss Post (the Swiss state-owned postal and digital-services operator) acquired a majority stake; as of 2026 Swiss Post is the sole shareholder, making Tresorit a fully Swiss-state-anchored entity. This pushes the directory's other (Switzerland) classification into the highest end of that tier: Swiss jurisdiction with state-owned parent is structurally as close to "sovereign" as a vendor can credibly claim. The compliance footprint matches: ISO/IEC 27001:2022 certified by TÜV Rheinland (covering sales, development, maintenance, and support of E2E-encrypted cloud services), plus alignment with GDPR, HIPAA, ITAR, FINRA, CCPA, CJIS, DORA, NIS2, and TISAX, an unusually broad regulated-industry coverage including US healthcare (HIPAA), US defence-export controls (ITAR), US financial markets (FINRA), and US criminal-justice systems (CJIS) for the rare global customers who need that combination on top of a Swiss-jurisdiction base. Customer-selectable Swiss or EU data residency, contracts under Swiss law and the Swiss Federal Act on Data Protection.
Pricing in EUR: a Personal Plus tier starts at approximately €10/month for ~1 TB; Business plans start in the €14-30/user/month range across SecureCloud and Engage tiers; Enterprise is negotiated. Best fit: regulated enterprises (legal, financial-services, healthcare, defence), Swiss public-sector buyers, journalists and NGOs, and any organisation needing a Dropbox / Box / OneDrive replacement with mathematically-provable zero-knowledge encryption from a state-anchored Swiss vendor. Together with Proton Drive, Tresorit forms the directory's Swiss-encrypted file-sharing dual-pick; Proton wins on consumer / freemium and ecosystem breadth (Mail/VPN/Pass/Calendar/Docs), Tresorit wins on enterprise compliance breadth and the unique Swiss-Post state-owned governance.