Two things changed at once.

The first is velocity. Evaluating tools used to be a procurement decision. Now it is a browser tab, and the number of companies holding a credential of yours grows every week without a single deliberate choice being made.

The second is that AI tooling has an unusually young supplier base. That is not a criticism — it is what a fast-moving field looks like — but a company that shipped its first version this year has not had time to build the security posture of one that has been audited for a decade.

The threat side has also moved. IBM's 2026 Cost of a Data Breach research reports AI-driven attacks rising sharply and adding roughly a million dollars to the average breach, as attackers use the same tooling you do to make phishing faster and more personalised. Generic scam emails were easy to ignore. A message that correctly names a tool you use, in the register your suppliers write in, is not.

1. Own a domain. This is the foundational step and the one people skip, because it feels like something you do once you are "a real business". It is the opposite: it is the thing that makes everything after it possible. A domain costs about the same as a coffee per month and it means your identity is yours rather than rented from a mail provider.

2. Put your business email on it. Not a forwarding alias — actual mailboxes on your own domain. The practical payoff is that your business identity is now portable. Change providers, add a colleague, hand over an account: none of it touches your personal life.

3. Give every tool its own address. This is the part that turns the whole thing from tidy to genuinely useful. If each signup gets its own alias, then attribution becomes trivial — mail arriving at the alias you gave one vendor tells you exactly who leaked or sold it — and revoking access is deleting one alias rather than changing a password everywhere.

4. Stop reusing passwords. Obvious, and unachievable by memory at this volume. It requires a manager, and at sixty accounts it stops being optional.

Proton Mail for Business covers steps two and three: mailboxes on your own custom domain, end-to-end encrypted, with a business tier that adds domains and seats as you need them. The property that matters for this specific problem is the business model — Proton sells subscriptions rather than advertising, so the contents of your mailbox are not the product. When the concern is how much of your working life is legible to third parties, who profits from your inbox is a reasonable thing to care about.

Proton Pass for Business covers steps three and four together, and that combination is the actual reason to look at it here rather than at a password manager alone: it generates the alias and stores the credential in the same action. Creating a genuinely unique identity per tool becomes the path of least resistance rather than a discipline you have to maintain.

Check current Proton pricing directly — business plans start in the region of a few dollars per user per month and the tiers change, so a number quoted in an article is worth less than the page itself.

Where Proton is the wrong answer. If your team lives in Google Docs and Sheets all day, Workspace's integration is worth more than Proton's encryption and you should buy Workspace. If you need plain IMAP into arbitrary desktop clients, Proton's encryption model means going through its Bridge, which is a real extra step and irritating if your workflow depends on it. If you want a large ecosystem of third-party integrations wired into your mail, Proton's is smaller by design. And if you are looking for free business email, this is not that — the free tier is a personal account, and business use means paying per seat.

The honest summary: choose Proton when privacy is a requirement you can articulate, not because privacy sounds prudent. If you cannot say what you are protecting against, a cheaper provider with a domain attached still gets you most of the benefit described above, because most of the benefit is the separation itself.

If you only do two things: buy the domain, and stop using your personal address for tool signups. Everything else here is refinement. The separation is what shrinks the blast radius, restores attribution and makes an exit possible, and it is worth more than any particular provider you pick to implement it.

Figures are attributed inline where they appear: breach-cost figures are from IBM's 2026 Cost of a Data Breach research, and pricing should be checked against Proton's own pricing page, which changes.

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