Sending sensitive documents and information safely

Ordinary email is more like a postcard than a sealed letter: it passes through several systems on the way, it sits in two mailboxes indefinitely, and it is forwarded without a second thought. For most messages that is fine. For a scan of someone's passport, a payroll spreadsheet, a signed contract or your banking details, it is not. Here are the safer options.

Share a link instead of attaching

Save the file in OneDrive or SharePoint and share it with the specific person, as described in Sharing files safely. The recipient has to prove who they are to open it, you can see whether it was opened, you can set an expiry date, and you can take access away later. Nothing of value sits in anyone's inbox. For most business documents this is the right answer.

Encrypt the message

Microsoft 365 Business Premium and some other plans include message encryption. In Outlook, choose Options and then Encrypt before sending. The recipient opens the message through a secure page after confirming their identity, and you can prevent forwarding. If you do not see the option, ask us whether your plan includes it.

Protect the file itself

If a file must go as an attachment, protect it with a strong password in Word, Excel or your PDF software, and send the password a different way, by phone or text message, never in the same email or a follow-up email. This is weaker than the options above, but much better than nothing.

Banking and payment details

Never send or accept a change of banking details by email alone. Confirm it by phone with a person you know, on a number you already had. This one habit stops most invoice fraud, which is the most expensive scam affecting small businesses. See Spotting a phishing email.

What not to use

Text messages, personal email accounts, consumer chat apps and photos taken on a personal phone are not suitable for business documents containing personal or financial information. They leave copies in places your business does not control and cannot delete.

Receiving sensitive documents

If customers or applicants need to send you ID or forms, we can set up a secure way for them to do it, such as a request link from your SharePoint that lets them upload directly into a protected folder. Email hello@bitnode.tech and we will suggest the right option.