If errors on your VAT return are discovered by VAT officers, for example following a VAT visit, you may be charged interest and penalties.
If you discover an error yourself, and take steps to correct it, you may be charged interest but should avoid penalties.
If the error is for £2,000 or less, you can make the adjustment on your current VAT return.
For larger errors you do not adjust your VAT return but instead write to your local VAT office setting out full details of the error including:
You can also write instead of amending your VAT return for errors of £2,000 or less
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