Thank you for reaching out, Kaley.
Currently, the option to add tax amounts is unavailable in QuickBooks Online (QBO). The system is designed to comply with HMRC guidelines, which means it automatically calculates taxes based on the predefined rates assigned to each product or service.
However, we can add new tax rates for the different VAT levels applicable to your products or services. This will help ensure that the tax calculations align with the appropriate rates. Here’s how we can do that:
- Navigate to Taxes, the VAT.
- Click the Add tax button.
- Choose the type of tax you want to add.
- Provide a name for the new tax rate and other details in the description.
- Select the tax agency it applies to and enter the percentage rate.
- Hit Save once done.

After that, you can return to selecting tax rates for your line items.

Also, if you want these rates to be automatically applied when you select a line item for an invoice, go to the Products and Services page, then make Edit in the VAT section.

Once your customers pay their invoices, let's record the payment using the Receive payment feature in QuickBooks. This ensures the invoice is marked as paid.
You can also explore this article for a detailed breakdown of all VAT-related transactions, which will help you verify accuracy, detect errors, and prepare for audits: VAT Detail Report.
Please stay in touch and let us know in the comments below if you have further questions about your invoices, recording payments, or tax calculations in QuickBooks. We're here to help!