As of 13 August 2026, AI can only partly estimate your income tax for the year.
This still needs a person who signs their name to it.
Can you do it?
5 minutesto a draft.
30 minutesto something you’d act on.
Cost, all in£0
Skill neededchat-fluent
Who has to check ityou
What the alternative costsThe available tool information does not provide a comparable cost for an accountant or tax adviser.
If this goes wrong, you budget or pay based on a wrong estimate and may need to correct the position with HMRC.
What to actually do
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.
Use a tool built for this
Second choiceDo it yourself
The distant thirdA chat interface, chat-fluent skill, and roughly 30 minutes until you can act on the result.
How to actually do it
- Open the relevant GOV.UK and HMRC pages for the tax year and note the current income tax rates, allowances and treatment of each income type that applies to you.
- Gather your payslips, P60 or payroll summary, pension contribution records, bank interest statements, dividend records, self-employment accounts and records of tax already paid.
- Remove account numbers and other unnecessary private information, then put each income and deduction into a simple spreadsheet with its source, tax year and amount.
- Paste the prompt and the spreadsheet figures into a chatbot, including the exact tax year and any facts about employment, pension contributions, residence, benefits or self-employment.
- Check every rate, allowance, deduction and eligibility assumption in the response against the GOV.UK or HMRC pages you opened, and correct the calculation when any item does not match.
- Use the checked estimate for budgeting only, and send the figures and unresolved points to an accountant or tax adviser if the result will determine a Self Assessment return or involves unusual income or reliefs.
Prompt
Estimate my UK income tax for [tax year]. Use only the figures and facts I provide, and do not invent missing information. First list the information needed and identify anything missing. Then calculate the estimate step by step, separating employment income, self-employment income, savings income, dividend income, pension income and other taxable income where relevant. Show gross income, allowable deductions, taxable income, tax by band, tax already paid and the estimated balance or repayment. State every assumption, flag any figure that depends on an eligibility or tax-treatment judgement, and give a low and high result only where the difference follows from clearly stated assumptions. Do not guess current rates, thresholds, allowances or deadlines. If a current rule is needed, tell me exactly which GOV.UK or HMRC page I must check and pause that part of the calculation until I provide the relevant rule. This is an estimate, not a Self Assessment filing and not professional advice. Do not tell me to claim a relief unless you explain what evidence would be needed and mark the point for confirmation with HMRC or a qualified tax adviser.
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 whether an unusual payment, expense or relief receives the tax treatment you expect.
- AI cannot know whether your figures are complete when income comes from several employers, platforms, investments or businesses.
- AI cannot replace HMRC's calculation or confirmation of what you owe.
- AI cannot take responsibility for a wrong estimate, late payment or incorrect Self Assessment return.
- AI cannot make specialist judgement disappear when the calculation depends on facts you have not recognised as relevant.
What caps this at PARTLY: judgement under ambiguity, verification cost and stakes of error.
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 | 2 |
| Inputs | 1 |
| Verification | 1 |
| Liability | 1 |
| Effort delta | 2 |
| Total | 7 / 10 |
The methodology and its thresholds are published in full.
FAQ
- Can ChatGPT calculate my income tax?
- Yes, it can calculate an indicative UK estimate if you provide complete figures and the tax year. It can still apply a relief or income rule incorrectly, so compare its assumptions and arithmetic with HMRC guidance. This is not professional advice.
- What information does AI need to estimate my tax?
- Give it the tax year, each source of income, tax already paid, pension contributions, relevant benefits, deductions and any Self Assessment details. Include the source and date for each figure, but remove account numbers and unnecessary personal data. This is not professional advice.
- Can AI tell me how much tax I owe HMRC?
- It can estimate a possible balance from the figures you provide, but it cannot confirm the amount HMRC will charge. Check the result against your HMRC records and ask an accountant or qualified tax adviser about a serious or unusual case. This is not professional advice.
- Is it safe to use AI for tax advice?
- It is suitable for organising figures and explaining an indicative calculation, not for blindly deciding which reliefs or deductions you can claim. You remain responsible for what you report or pay, and a serious case needs an accountant or qualified tax adviser. This is not professional advice.
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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