Omnicron
Microsoft 365Difficulty: IntermediateEstimated time: 10 minutesUpdated

How to Check Microsoft 365 Sign-In Activity

Review recent sign-ins to your own account, or your whole organisation, to spot suspicious access early.

Why this matters

Sign-in activity shows when, where and from what device an account was used. Unexpected locations or failed sign-ins can be the first sign of a compromised account. Checking regularly helps you catch problems before they turn into fraud.

What you'll need

  • Your Microsoft 365 account
  • For organisation-wide logs: an admin role such as Security Reader or Global Reader

Step-by-step instructions

  1. Step 1

    Users: open My Sign-ins

    Go to mysignins.microsoft.com and select "Recent activity".

  2. Step 2

    Users: review each sign-in

    Expand entries to see the location, device, browser and whether it succeeded. Select "Looks good" or "This wasn’t me" for unusual entries.

  3. Step 3

    Admins: open the Entra sign-in logs

    Go to entra.microsoft.com, then Identity, Monitoring & health, Sign-in logs.

  4. Step 4

    Admins: filter the results

    Filter by user, date range, status (failure) or location. Look for sign-ins from overseas, unfamiliar apps or many failures in a short time.

  5. Step 5

    Admins: check risky sign-ins

    If you have Microsoft Entra ID P1/P2 (included in Business Premium for P1), review the Risky sign-ins and Risky users reports.

  6. Step 6

    Act on anything suspicious

    Reset the password, revoke sessions and check mailbox rules for any account with unexplained sign-ins.

Summary

A quick monthly review of sign-in activity, and an immediate check when something feels wrong, helps you spot compromised accounts early.

Still Need Help?

Some IT problems are easier to solve with a professional. If you've followed the guide and still need help, the Omnicron team can assist.

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