I tried to migrate from Desktop for Mac to QB Online and I canceled the subscription. Now, I'm trying to purge the data file and it says I can't because of the sub tier.

Let's go through the process on how purging a company file works in QuickBooks, Mike.
 

First off, you cannot purge a canceled company because it will be automatically deleted after a year. Additionally, if you have canceled your QuickBooks Desktop subscription but your QuickBooks Online account is still active, you cannot purge your data if you are using QuickBooks Online Simple Start, even if the data is less than 60 days old.

Additionally, in case you need guidance on how your features and data move from QuickBooks Desktop (QBDT) to QuickBooks Online (QBO), feel free to visit this article: Understand how your features and data move from QBDT to QBO.

If you have any further questions or concerns about managing your company file, please don't hesitate to reach out. We're here to assist you.