Correcting VAT Errors
Most VAT errors can be amended by making an adjustment on the next VAT return. This method is for errors of a net value that do not exceed £10,000, or errors of a net value between £10,000 and £50,000 which do not exceed 1% of the box 6 (net outputs).
Where errors cannot be amended this way, HM Revenue & Customs’ guidance now includes details on how to use the online form to make the correction. Details can be found here.