Mailbox Security for Business Email Accounts
Protect company mailboxes with a repeatable plan for authentication, account recovery, app access, forwarding rules, offboarding, and response.
Business email security depends on more than choosing a difficult password. Each mailbox connects people, devices, recovery channels, applications, and business processes. A weakness in any one of those areas can expose messages, contacts, invoices, or password-reset links.
Use the following controls to reduce account takeover risk while keeping legitimate access manageable.
Start with unique accounts and strong authentication
Give every person an individual account. Shared passwords make it difficult to determine who accessed a mailbox, remove one person's access, or investigate an incident. If several employees need the same address, use delegated access or a shared mailbox with named users instead.
Your business email account structure should distinguish between personal mailboxes, shared operational addresses, aliases, automated senders, and administrator accounts. Administrators should have separate privileged identities rather than using everyday mailboxes for high-risk configuration work.
Require a unique password generated and stored in an approved password manager. Long, random passwords are preferable to predictable variations based on company names, seasons, or employee details. Block known-compromised passwords if your email system supports that control.
Enable multi-factor authentication for every interactive account. Prefer phishing-resistant security keys or passkeys for administrators, finance staff, executives, and anyone able to change domains or routing. Authenticator apps are a reasonable alternative; SMS should generally be a fallback rather than the primary factor.
Secure recovery before it becomes an emergency
Account recovery can bypass an otherwise strong password and MFA setup. Review recovery methods as carefully as sign-in methods.
Use company-controlled recovery addresses and phone numbers where possible. Avoid relying on an employee's personal email account, especially for administrators. Store emergency recovery codes in a restricted business password vault, not in the mailbox they recover or on an unencrypted local file.
Define who may approve a reset and what evidence is required. A message from a new phone number or an urgent request from a senior employee is not sufficient verification. Use a second trusted channel, such as a known internal number or an in-person check. Record significant recovery actions so they can be reviewed later.