Hi andrew24,
Welcome to the community!
When you enter transactions using a sales VAT code (e.g. an invoice with 20% S) these will automatically pull through to the open VAT return and show in VAT reports.
If you are on the cash based VAT accounting scheme, the VAT element of the sale will only show in the return when the transaction has been closed - i.e the bill or invoice has been paid.
You can see more on VAT codes in QuickBooks here.
Thanks!
