Quickbooks Online ...anyone have good luck transferring all the data to the online version?

If you mean from QuickBooks Desktop, then no almost no one has had luck with that because the transfer is by design incomplete. Online leaves a long list of things behind - something for you to fix manually.

@Quickuser3 

What data type are you missing? For example, you cannot migrate attachments files. You can use the trial version to access your historical data for good.

All the accounts were not transferred and some Bank accounts were showing a balance and the accounts were closed for a few years. A frustrating experience.

Some Bank accounts were transferred with a balance although they had been closed and should have shown a zero balance.  Data was not all transferred.  

thank you. That is what I thought and why I don't want to use the online version.

The online Quickbooks desktop price for 2025 has increased to $999 for a year.  That's absurb!  I talked to a representative and she said since I have 2024 version it will not provide what I need and must renew at their new price. I am looking for another option at this time and refuse to pay $999.  I paid $649 for the 2024 and thought that was too much to pay.  I'm disappointed with Intuit Quickbooks exhorbitant price increase.

Well,  the 2025 Quickbooks desktop version is $999.  That makes me upset.   2024 was $649.  Talked to a rep. and she said I would not be able to use 2024 and do everything with it.  I'm looking at other options at this time. Since the online version does not transfer all data correctly, it might be best to use another vendor's software or many Quicken which is under $80.

You can use QB Desktop with a non subscription license if you don't need to run any add-ons.