I've invoiced a customer £47.95Made up for £39.95 in sales and £7.99 in VAT so the total amount comes out at £47.94.Any idea why there's a difference?

You're correct that the sum of the item and VAT is £47.94, @BigBen. You can communicate with our experts to verify the difference between the invoice amount and the total sale with VAT.

Correct computation of the values on your invoices is significant for recording and customer-seller relationships. Since you're experiencing a calculation issue, I suggest contacting support directly. They can investigate this further and provide resolutions accordingly.

Follow the steps below:

1. Navigate to the Help icon at the top right-hand corner.
2. Select Search, then press the Contact Us button.
3. Enter your concern in the box and hit Continue.

Please note our support hours on this article so we can address your concerns promptly: QuickBooks Online Support. 

Here's a reference for personalising your sales forms: Customise invoices, estimates, and sales receipts in QuickBooks Online.

Once done, follow this guide to enter customer payments in the program: Record invoice payments in QuickBooks Online.

We aim to ensure the accurate amount reflected in your sales transactions. You can also ask follow-up queries concerning receivables. I'll be here to assist you.