As of 13 August 2026, AI can only partly calculate VAT on your UK business sales.

What to actually do

1. Hand it to a person

   The route this page recommends

   Someone with a licence or accountable authority has to sign this before it counts.

2. Use a tool built for this

   Second choice

3. Do it yourself

   The distant third

   A chat interface, chat-fluent skill, and roughly 30 minutes until you can act on the result.

   How to actually do it

   1. Open your sales ledger, invoices and credit notes for the period, and export or copy the transaction details into a spreadsheet.
   2. Add columns for invoice date, tax point, customer location, description, net amount, VAT amount, gross amount, currency and any VAT treatment already recorded.
   3. Open your VAT registration details and accounting scheme information, then gather the relevant HMRC guidance for unusual, overseas, exempt, zero-rated or reverse-charge sales.
   4. Paste the business details, HMRC links and sales table into the prompt, keeping separate rows for credit notes, refunds and corrections.
   5. Ask the AI to calculate each row and reconcile its total with the sales ledger total, then copy its result into a review spreadsheet.
   6. Compare every VAT treatment marked uncertain against the supplied HMRC guidance and ask an accountant to resolve any item the AI has flagged or any treatment you cannot explain.
   7. Use the checked totals in your bookkeeping records, retaining the source invoices, assumptions and accountant's corrections with the period's VAT working papers.

   Prompt

   Calculate the VAT on the UK business sales data below. Do not invent missing facts or choose a VAT treatment without evidence. First identify the business VAT scheme, VAT registration status, invoice dates, tax points, customer locations, goods or services supplied, VAT rates already shown, whether prices are VAT-inclusive or VAT-exclusive, and any credit notes, deposits, exemptions, zero-rating, outside-the-scope items, reverse-charge transactions or partial exemptions. Use only the information I provide and the HMRC guidance or links I provide. For each sale, show the net amount, VAT amount, gross amount, VAT treatment, calculation and any assumption. Separate certain calculations from items needing an accountant or confirmation from HMRC. Then give totals by VAT treatment and an overall total. Check that the figures reconcile to the sales records and flag duplicate, missing or contradictory entries. Do not prepare or submit a VAT return, and do not give professional advice.
   
   Business VAT details:
   [Paste your VAT registration status, VAT scheme, accounting basis and relevant HMRC guidance or links]
   
   Sales records:
   [Paste a table or upload the sales data, including invoice date, tax point, customer location, description, net or gross amount, VAT shown, currency and credit notes]

   Open it prefilled in ChatGPT or Claude, or copy it into Gemini, which takes no prefill link.