Need to Restore PST Files to Office 365 Mailboxes - What's the Best Approach

For a one-time PST restoration into existing Microsoft 365 mailboxes, Microsoft Purview is usually the first option I would evaluate because it keeps the import, compliance roles, and destination tenant in one Microsoft-managed workflow. If this is a recurring migration project, involves many tenants, or needs a service provider to manage complex batch work, a paid platform such as BitTitan MigrationWiz can be worth comparing.

The difference is not simply free versus paid. Purview may be the better choice when the main concern is governance and you can accept the setup and role requirements. MigrationWiz may reduce operational effort for a large, repeatable project, but it adds licensing cost and another vendor to the process. In either case, run a pilot mailbox, validate folder mapping and date ranges, and retain the source PSTs until users confirm the restored data.