Gmail to Exchange Online Migration Mailbox limit

Copper Contributor



I have a client who is looking to migrate from Gmail/G-Suite to Exchange Online however they have 50-60 Mailboxes that are over 100GB. These mailboxes are large as they have to keep the data in these mailboxes for 3-5 days.


Is it possible migrate mailboxes larger than 100GB to Exchange Online?


Please advise

2 Replies

Hey @Dhillan Kalyan 


O365 supports 100 GB primary mailbox only. However you can enable archive and inject data into it and technically  for Exchange Online Plan 2, you should be able to inject unlimited data into archive mailbox.


Hope this helps !!!


@Dhillan Kalyan AFAIK up to 120 GB will work as well for migrations. If you are using native tools / IMAP migration within the Microsoft 365 Admin center, there is no chance to ingest it to the archive mailbox. If you're using a third-party vendor or any EWS-tools, you can ingest the data also directly into the archive.