To set up EC VAT in QuickBooks Online (QBO), follow these steps below:
1. Go to the Taxes on the left pane, then click the Set up VAT button.
2. Select the beginning month of your current VAT period on the Set up VAT window.
3. Choose your filing frequency and VAT accounting scheme.
Standard - also known as accrual, select this option if you count your income when you invoice your customer.
Cash - select this option if you count your income when you receive money from your customer.
4. Enter your VAT registration number, then put a checkmark on Flat Rate Scheme (FRS), if your business is entitled to this.
5. Click Save. Your VAT codes will now be automatically set up.
That should do it. For additional resources, I recommend checking out these articles: