Submitted incorrect VAT Return. How can I change?

[Joshuaneale]

Hello

I mistakenly hadn’t included an invoice before submitting my return ho can I add the new invoice and submit an amended return?

[QFSteve]

Hello Joshua

Once a return is finalised and submitted it can not be amended.
You can enter the invoice as normal and it will be picked up by the next return you submit.

[ian_roberts]

And this approach (leave the existing return alone and include the missed invoice in your next return) is actually the HMRC approved way to sort it out unless the error means you’ve underpaid VAT by several thousand pounds.

Reporting threshold

You can adjust your next VAT Return if the net value of the errors is £10,000 or less.

You can also adjust your next VAT Return if your error amount is up to 1% of your box 6 figure (up to a maximum of £50,000).

You must report the error to HMRC if it’s above the reporting threshold.

Reference