Secure Mail
When email isn't enough
How Secure Mail works
- 01
Send as secure mail
The message and attachments go to a protected portal — the recipient gets a personal link.
- 02
Verify with a one-time code
The recipient opens the message with a code sent to their email. No account needed.
- 03
Read and sign
Documents are read and signed in the same portal — with strong bank authentication when required.
The recipient's journey
Link → code → document → signature — in half a minute.
Illustration: the recipient opens a secure mail via a personal link, verifies with a one-time code, reads the document and signs it, after which the signature is sealed.
No account required
An email address is all the recipient needs — the threshold stays low.
One-time codes
The link is personal and opens only with a code that stays valid for 10 minutes.
Sealed signatures
The finished document is sealed with an attached signature certificate — every party gets a copy.
Full audit trail
Every open and every signature lands in the event log.
A signature that stands up to scrutiny
Signing works on two levels: an electronic signature given by typing your name, or strong bank authentication where the signer's identity is verified with bank credentials. There can be several signers — all at once or in a set order, where the next invitation goes out automatically once the previous signer has finished. Signers can also carry rules: a guardian, for example, must be an adult and a different person than the minor the consent concerns.
Once everyone has signed, the document is sealed: each signer's name and timestamp are stamped onto the document, and a signature certificate is attached recording name, signing method, IP address, timestamp and the consent text. A SHA-256 fingerprint is computed over the whole document and pinned to the exact template and version used at signing time. The final PDF is written once and can never be re-sealed — and every party receives a copy by email.
- One-time code
- 10 min · single-use
- Personal link
- 30 days
- Attachments
- 50 MB / file
- Encryption
- AES-256 + TLS
Verified on 22 July 2026
Security without the fine print
Messages and attachments are encrypted at rest with AES-256 and in transit with TLS. The one-time code is six digits, single-use, and locks after five wrong attempts. The personal link is randomly generated, valid for 30 days, and scrubbed from the browser's address bar the moment it opens. Attachments up to 50 MB per file — PDFs, Word and Excel files, images and ZIP archives.
The same secure mail we use ourselves
Secure Mail isn't a bolted-on product — it's the same infrastructure Truster uses for its own sensitive deliveries: employment contracts are signed through it, a guardian's consent for an under-age worker is requested with it, and accountant-signed company reports and certificates travel the same route. If it stands up to our own contract and authority processes every day, it will stand up to yours.
Start communicating securely today
Secure Mail is included in every For Companies package.