How do i do a vat adjustment for invoices entered late ie after the vat return has been filed ?

Hi westernhydraulic,

You can enter the transactions with the correct date of the previous filing period. This lets QuickBooks Online (QBO) accounts the VAT due on your current return as an exception. Let me provide you more information so you'll be able to enter them correctly.

The exception will notify the tax agency that the transaction has been accounted for within the current period but refers to a previously filed period. This will not alter the filed return. 

Also, this will show changes but will net out to zero once you delete and recreate transactions for the previous period. This is normal not to affect the balance of your filing. 

Here's how to view the exception report:

1. Click Taxes in the left menu.
2. Click Prepare return drop-down arrow, select View exception details.
3. Click Run report.

Please check this link in case you have other questions about taxes: Help Articles For Taxes.

Let me know if you need anything else. I'm always here to help.