As of 13 August 2026, AI cannot complete your HMRC Self Assessment tax return.
This still needs a person who signs their name to it.
Can you do it?
15 minutesto a draft.
n/ait cannot be self-verified.
Cost, all in£0
Skill neededchat-fluent
Who has to check ita professional
What the alternative costsNo priced human alternative is listed in the supplied data.
If this goes wrong, you submit an incorrect return or claim an unsuitable relief and remain responsible for the consequences with HMRC.
What to actually do
Hand it to a person
The route this page recommends
Someone with a licence or accountable authority has to sign this before it counts.
Use a tool built for this
Second choiceDo it yourself
The distant thirdA chat interface gets you a draft, but you cannot verify it yourself. That is the catch.
How to actually do it
- Open your HMRC online account and the relevant Self Assessment return, but do not submit anything.
- Gather your P60 or payslips, self-employment records, invoices, bank statements, rental records, pension documents, gift aid records and details of tax already paid, keeping the original documents available.
- Remove unnecessary personal identifiers from copies, then paste the prompt and the relevant figures or document text into a chatbot in separate labelled sections.
- Ask the chatbot to produce a missing-information list and a table mapping each supplied figure to the proposed HMRC section, with no estimates or invented entries.
- Compare every proposed figure with the original documents and mark every uncertain tax treatment, relief or allowance instead of accepting it.
- Check the uncertain items and the completed draft with a qualified UK accountant or tax adviser, then enter only the confirmed answers into HMRC and retain the supporting records.
Prompt
Help me prepare, but not file, my UK HMRC Self Assessment tax return for the tax year [tax year]. I am a [sole trader/employee/landlord/other]. Use only the documents and figures I provide. First list the information that is missing, inconsistent or unclear. Then organise my income, expenses, pension contributions, tax already paid and other figures into the sections they may relate to. Do not invent, estimate or round figures, and do not decide that I qualify for a relief or allowance. For every item that could have more than one tax treatment, explain the uncertainty and tell me to check GOV.UK or ask a qualified UK accountant or tax adviser. Keep a separate list of figures I must verify against the original documents. Do not submit the return, claim that it is correct, or give professional advice.
Open it prefilled in ChatGPT or Claude, or copy it into Gemini, which takes no prefill link.
What it gets wrong
- AI cannot reliably decide which expenses, reliefs or allowances apply to your circumstances.
- AI cannot confirm that you have found every source of taxable income or supplied the correct tax-year figures.
- AI cannot take responsibility for the return after you submit it.
- AI cannot replace an accountant or tax adviser when an entry has an uncertain or complex tax treatment.
What makes this a NO: legal accountability, regulated advice and verification cost.
How we scored this
Five axes, each scored nought to two by hand: ten means AI carries the task cleanly, and the thresholds that turn a total into YES, PARTLY or NO are published in the methodology. Each axis name links to its definition.
| Axis | Score (0–2) |
|---|---|
| Output | 1 |
| Inputs | 1 |
| Verification | 0 |
| Liability | 0 |
| Effort delta | 1 |
| Total | 3 / 10 |
The methodology and its thresholds are published in full.
FAQ
- Can ChatGPT complete my HMRC Self Assessment tax return?
- No. It can sort information and draft a checklist, but it cannot reliably determine the correct tax treatment or accept responsibility for what you submit. This is not professional advice, and a serious or complex case needs a qualified UK accountant or tax adviser.
- Is it safe to use AI for my UK tax return?
- Use it for document organisation and arithmetic transcription only, not as the final decision-maker. An incorrect relief or omitted income can leave you responsible to HMRC, so uncertain entries need checking with a qualified UK accountant or tax adviser.
- What can AI do for my Self Assessment tax return?
- It can turn supplied records into a list of figures, identify missing information and map entries to possible return sections. It cannot establish that the figures are complete or that a relief applies, and it must not be allowed to submit the return.
- Should I use an accountant for my Self Assessment tax return?
- Use a qualified UK accountant or tax adviser if your income, expenses, property, investments or reliefs are not straightforward, or if you cannot verify the treatment yourself. They can check the return and explain which information and records HMRC requires.
Nearby answers
Assessed by gpt-5.6-luna (gpt-5.6-luna) on 2026-08-13, second-checked by an independent model. Wrong somewhere? Email [email protected] and it gets re-checked.
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