Every accountant handles the same paradox. The information your clients trust you with, their Social Insurance Numbers, T4s, banking details, and full financial statements, is exactly the information criminals want most. And for most firms, that information still moves through the least secure channel available: email.
This guide covers what is actually at risk, why the usual fixes fall short, and a practical way to exchange client documents that keeps their data confidential and your firm defensible.
Why email is the weak link
Standard email is not encrypted end to end. A message can be intercepted in transit, it sits in plaintext on several servers, and it exposes metadata such as sender, recipient, and subject line even when the body is protected. Once you press send you cannot recall the message, expire it, or see who opened it. A T4 you emailed in February is still sitting in an inbox in November.
For an ordinary business that is a bad habit. For an accountant it is a professional liability, because the data is not yours. It belongs to your client, and privacy law now treats it that way.
What "secure" actually requires
Three things separate genuinely secure document exchange from security theatre:
- Encryption on the device, not just in transit. Many tools encrypt files while they travel and while they sit on a server, but the provider can still read them. Client-side encryption scrambles the file on your device before it is uploaded, so no one in the middle, including the vendor, can open it.
- Control that survives the send. You should be able to set an expiry, limit how many times a document can be opened, and revoke access after the fact.
- No friction for the client. The most secure portal in the world fails if your client will not log into it. The best tools let the recipient open a file without creating an account.
A practical workflow
Use an end-to-end encrypted send tool for exchanging documents. You encrypt the file with a passphrase in your browser, send the link, and share the passphrase through a separate channel such as a text message. Your client opens it with no account and no software. Set an expiry so the document does not linger.
For files you keep on hand, such as working papers and prior returns, store them in an encrypted vault where you control the keys, and keep them on Canadian servers under Canadian law where you can. If the vault sits in a connected Google Drive or OneDrive, data residency follows that provider.
Where Privatt fits
Privatt was built for exactly this. Send lets you send an encrypted document to any client with no account on their end, and the Vault modes where you hold the keys encrypt client files on your device before they are stored, so what reaches our servers is unreadable. The one exception is the Privatt-managed mode, which trades that for malware scanning, and we say so plainly.