We recommend an %BRAND_EXCHANGE_ONLINE_SHORT% cutover migration when you want to move your on-premises mailboxes to %BRAND_OFFICE_365_SHORT% ...

We recommend an %BRAND_EXCHANGE_ONLINE_SHORT% cutover migration when you want to move your on-premises mailboxes to %BRAND_OFFICE_365_SHORT% and manage them in the %BRAND_OFFICE_365_SHORT% admin center. A cutover migration enables you to move your entire email organization to %BRAND_OFFICE_365_SHORT% over a few days. Even though a cutover migration supports moving up to 2,000 mailboxes, due to length of time it takes to create and migrate 2,000 users, it is more reasonable to migrate 150 or fewer users. To learn more, see What you need to know about a cutover email migration to %BRAND_OFFICE_365_SHORT%.