How can I transfer data BACK from QB Online UK to QB Desktop 2020?

Hello, @peter63.

There's no direct way to transfer your QuickBooks Online company data to QuickBooks Desktop. You'd have to export your data and import it in QuickBooks.

Here's how:

1. Log in to your QuickBooks Online account.
2. Go to the Settings ⚙ icon.
3. Select Export Data. 

Once exported, you can review each file then import it. Depending on the information, there are different ways to import your data.

• With MS Excel
• Using CSV files
• Import and export invoice and other form templates
• Import and export IIFs
• Import bank transactions with Web Connect files
• Send journal entries back and forth with your accountant
• Export your file for your accountant and import accountant changes 

Let me know if you have other questions about managing your QuickBooks company file. 

@peter63 

You need a 3rd migration tool to do so. i.e TP Exporter for QBO and TP Importer for QBD

https://transactionpro.grsm.io/qbo