As of 13 August 2026, AI can only partly check whether you are due a tax refund.

What to actually do

1. Hand it to a person

   The route this page recommends

   A person who owns the outcome does this end to end, worth it when the failure is dear.

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. 1. Open your HMRC online tax account and note the tax year, pay, tax deducted and PAYE codes shown there.
   2. 2. Gather the relevant P60, P45, payslips, pension statements, HMRC coding notices and records of other income or tax-deductible expenses.
   3. 3. Remove National Insurance numbers, tax reference numbers, bank details and other unnecessary personal data, then enter the remaining figures in the prompt.
   4. 4. Paste the prompt into ChatGPT, Claude or Gemini and ask it to use current GOV.UK or HMRC guidance available on 2026-08-13.
   5. 5. Compare every figure in the response with the original document and your HMRC tax account, and mark any assumption or missing figure that does not match.
   6. 6. For a difference or an unclear rule, check the cited GOV.UK page and contact HMRC or a qualified tax adviser before making a refund claim or changing a tax return.

   Prompt

   I am a UK taxpayer and want to check whether I may be due a tax refund for [tax year]. Use only the information I provide and current GOV.UK or HMRC guidance available on 2026-08-13. Do not invent figures, allowances, deadlines or tax rules. Do not assume that I am entitled to a refund.
   
   My circumstances and figures are:
   [Paste a plain-language summary of your employment, pension, benefits, other income and relevant expenses.]
   
   My documents say:
   [Paste relevant figures from payslips, P45s, P60s, HMRC coding notices, pension statements and other records. Remove National Insurance numbers, tax reference numbers, bank details and other unnecessary personal data.]
   
   Please:
   1. List the figures you used and match each one to its source document.
   2. Show the calculation step by step, separating confirmed figures from estimates and missing information.
   3. Say whether the evidence suggests a refund, no refund or an amount owed, and give the result as an estimate only where the evidence is incomplete.
   4. Explain which assumptions or UK tax rules affect the result, with a GOV.UK or HMRC source for each rule.
   5. Identify every missing document or figure that could change the result.
   6. Give me a short checklist for comparing this analysis with my HMRC online tax account.
   7. Do not tell me to submit a claim or amend a tax return until the figures have been checked against HMRC. State clearly that this is not professional advice and tell me when I should ask HMRC or a qualified tax adviser to check it.

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