The retention period for user sign-in logs in the Azure portal depends on the Azure Active Directory (AAD) pricing tier that you have.
In the Free and Basic tiers, sign-in logs are retained for 30 days.
In the Premium P1 and P2 tiers, sign-in logs are retained for 90 days.
In the Azure AD P2 and Azure AD P3 tiers, sign-in logs are retained for 180 days.
If you have an Enterprise Agreement (EA) or an Azure AD Premium P3 with an EA add-on, you can use the Azure Log Analytics service to retain sign-in logs for up to 730 days.
You can view the user sign-in logs by navigating to the Azure portal and going to Azure Active Directory > Authentication methods > Authentication logs. You can filter the logs by date range, user, and other criteria to find the specific sign-in events that you are looking for.
