HMRC AI Chatbot Tax Rules: Could the Taxman Ask to See Your ChatGPT History?

HM Revenue and Customs could ask to see the AI chatbot conversations taxpayers used to work out their tax figures, under proposed new powers in the Finance Bill 2026–27 that were reported on Wednesday 11 November 2026. The plans would modernise the tax authority’s powers over digital records, but HMRC has stressed it would still need an existing lawful basis before requesting any information.

The proposals centre on updating Section 114 of the Finance Act 2008, the law governing computer records, and reforming information powers under Schedule 36 of the same Act. The government says the changes reflect how tax information is now created, stored and processed through software, automated systems and cloud-based services, rather than on paper.

HMRC AI Chatbot Tax Rules — Quick Reference Summary

What the proposed powers would actually cover

The draft legislation would update Section 114 so it works in a modern digital tax system, covering information held in digital and electronic form. HMRC would be able, where it already has the legal right to request information, to obtain and understand relevant material held within digital systems, including records managed by third-party software providers.

The same measure reforms Schedule 36, which governs how HMRC requires information and carries out inspections for tax checks. It would also extend Financial Institution Notices to cryptoasset service providers. The government has been careful to say the changes do not create a new standalone information power: Section 114 would remain a supporting provision, used only where HMRC already has a lawful basis under Schedule 36.

That distinction matters for the chatbot question. The draft does not explicitly mention ChatGPT, Claude, Copilot or any other generative AI chatbot. Tax advisers say the broadened wording could still let HMRC ask for AI chats, prompt histories and working papers that were used to produce a tax figure — but whether that happens in practice remains uncertain, and no start date has been confirmed.

Why ChatGPT chats entered the tax debate

Millions of people now use AI tools to prepare Self Assessment returns, calculate liabilities and identify allowable expenses. Reporting on 11 November 2026 raised the question of whether those conversations could become disclosable if HMRC opened an enquiry into a return.

HMRC has already warned about the limits of AI in tax work. In January 2026 it published guidelines for software developers using generative AI in tax products, warning about inaccurate answers — which it calls “hallucinations” — and asking products to flag complex areas and suggest a qualified tax professional.

The concern is practical as well as legal. If a chatbot invents a relief, misreads an expense rule or uses the wrong year’s figures, the return that is filed is still wrong. HMRC told Which? that customers “remain responsible for the accuracy of their tax return”, including those who use AI, and that they should check it carefully before filing.

You still own the mistake: AI errors and the penalty risk

An error caused by an AI tool does not move responsibility away from the taxpayer. HMRC’s penalties factsheet says no penalty is charged where a person took reasonable care, while an error counts as “careless” when that care was not taken. A careless error can cost between 0% and 30% of the extra tax due if the taxpayer discloses it before HMRC finds it, and 15% to 30% if disclosure comes after HMRC has found it or is about to.

No tribunal has yet ruled on whether relying on a chatbot’s figures counts as reasonable care, and neither the factsheet nor HMRC’s Compliance Handbook mentions AI chatbots. Tax advisers say the safest course is to treat AI output as a draft: check every figure against source records, keep the workings, and get professional advice on anything uncertain.

It is the same direction of travel as other government data powers reported this week. The Department for Work and Pensions is separately introducing bank-account checks under its Eligibility Verification Measure, with the first notices sent in late October 2026, as departments modernise how they verify claims and returns.

What happens next before the rules take effect

Nothing in the proposals is in force yet. The Finance Bill 2026–27 was introduced in Parliament on 3 November 2026, and the measures would take effect on and after Royal Assent. If the Bill passes in the usual way, that points to 2027, according to tax insurance provider Qdos.

Professional bodies have already pushed back on the breadth of the draft. The Institute of Chartered Accountants in England and Wales urged a narrower definition of cryptoasset service providers and an explicit requirement for human authorisation of financial information notices. A crypto tax software provider argued in its consultation response that the draft definition could sweep in firms that only advise, rather than hold customer assets.

For taxpayers, the immediate message is unchanged: AI tools can help organise records and draft a return, but they cannot sign it, verify it or take responsibility for it. With the Self Assessment deadline of 31 January 2027 approaching, anyone who used a chatbot to prepare a return should keep the conversation history and the workings behind every figure — the same records HMRC may one day be able to ask for. The government’s policy paper on reforming information powers sets out the full proposals, and Business Matters reported the expected 2027 timetable for the new inspection powers.

Frequently asked questions

Can HMRC read my ChatGPT chats?
Not routinely. Under the proposals, HMRC could only request chatbot conversations where it already has a lawful basis to do so, such as an enquiry into a tax return. The draft legislation does not explicitly name ChatGPT, Claude or Copilot, and HMRC says it will not routinely inspect private AI conversations.

When would the new HMRC AI chatbot tax rules take effect?
The changes are in the Finance Bill 2026–27 and would take effect on and after Royal Assent. If the Bill passes in the usual way, that points to 2027. Nothing is in force yet.

What law is being changed?
Section 114 of the Finance Act 2008, which covers computer records, and the information and inspection powers under Schedule 36 of the same Act. The policy paper “Reforming information powers and modernising computer records law” was first published on 13 July 2026 and updated on 3 November 2026.

If ChatGPT gets my tax return wrong, who pays?
You do. HMRC told Which? that customers remain responsible for the accuracy of their tax return, including where AI was used. A careless error can attract a penalty of up to 30% of the extra tax due.

Should I keep my AI chatbot tax chats?
Yes. Keep the conversation history and the workings behind every figure in your return. They are part of your tax records, and under the proposed powers they are the kind of material HMRC could ask to see during an enquiry.