Should UK sole traders use AI for bookkeeping, MTD and self-assessment?

A chat tool can tidy a list of expenses you already wrote down. It cannot file your tax, and it is not the digital record HMRC means. If you are a sole trader, the question is not whether the tool is clever. It is whether you are about to let it invent a mileage figure or tell you that you are exempt.

Shaun, 20+ years in UK construction, keeps the invoices and the bank lines as the record, and uses a chat tool only to turn notes into plain questions. We search the AI world every week so you don't have to. The rules below are the ones on GOV.UK. If your year is unusual, use HMRC's checker rather than a paragraph on this site.

Who Making Tax Digital is for

HMRC's guide (opens in a new tab) says you need to use Making Tax Digital for Income Tax if you are a sole trader or a landlord registered for Self Assessment, you get income from self-employment or property or both, and your qualifying income is over the threshold for that tax year.

The same page sets the start dates it was publishing when this was written:

• Over £50,000 of qualifying income for the 2024 to 2025 tax year: you should have started from 6 April 2026. You can still sign up if you have not.
• Over £30,000 for the 2025 to 2026 tax year: from 6 April 2027.
• Over £20,000 for the 2026 to 2027 tax year: from 6 April 2028.

HMRC's agent planning page (opens in a new tab) describes that qualifying income as combined gross income, before expenses and tax, from self-employment and property. The exact test is HMRC's. Use the checker on the guide above, which also asks about exemptions. Do not ask a chat tool to decide the threshold for you. Paste nothing into it until you have read the result of that checker.

HMRC says it reviews your return and writes if you are over the line, and that not getting a letter does not remove the job of checking. You still send a Self Assessment return for the tax year before you start Making Tax Digital. Partnerships are not on this timetable yet. HMRC says it will set that out later.

There are exemptions, including where someone is digitally excluded. The list and how to apply are on GOV.UK, linked from the same guide. A chat tool cannot grant one.

What you actually have to keep

If you are in Making Tax Digital for Income Tax, HMRC wants digital records in software that works with the service, and quarterly updates from that software. The guide to using the service (opens in a new tab) is the page that sets the steps. For people who had to start in April 2026, that guide gives update deadlines of 7 August 2026, 7 November 2026, 7 February 2027, and 7 May 2027, then the tax return through the software by 31 January 2028. If your start date is later, do not copy those deadlines onto your year. Read the page for the year you are in.

A chatbot is not that software. Turning a photo of a receipt into a sentence does not file an update. Typing your takings into a free chat does not store them for the years HMRC expects. If your software changes, HMRC says (opens in a new tab) you still need to keep the digital records for at least 5 years from the submission deadline for each tax year. Their example: a 2026 to 2027 return submitted by 31 January 2028, records kept until at least 31 January 2033. Keep them in the software, or in the export your software gives you. Do not keep them only in a chat.

VAT is a different scheme. If you are VAT registered, follow the VAT Making Tax Digital rules for the VAT return. Do not assume the income-tax dates above cover the VAT return. They do not.

What a chat tool is fit for

Use it on notes you already made, to get a list you then type into the real software. Categories you use yourself: materials, fuel, insurance, tools, subcontractors. If you are not sure a cost is allowable, the tool must not decide. It can draft the question you will ask an accountant or HMRC's own guidance.

Sort these notes into a list I can type into my own records. UK English. Use pounds. Do not invent amounts, dates, or suppliers. Do not say whether an item is allowable for tax. If a figure is missing, write [amount].

Categories I use: [for example materials, fuel, insurance, tools, subcontractors]
Notes: [paste only the lines you are happy to share]

Do not paste your UTR, your National Insurance number, a full card number, or a customer's bank details into the prompt. A job name and a figure is enough. If a line is a cash job you have not invoiced, it still belongs in your records. Do not ask the tool how to leave it out.

Questions, not a tax return

When a GOV.UK page is hard to read, paste the relevant short section and ask for plain English. Then check the plain English against the page. Do not ask "what can I claim on a van" with no page in front of you. You will get a confident essay that may not match your year.

Explain this GOV.UK text in plain English for a UK sole trader in the construction trades. Do not add rules that are not in the text. If the text does not answer my question, say so.

My question: [one line]
Text:
[paste a short section from the GOV.UK page, with the URL noted in your own records]

Keep the URL in your notes next to the answer. If you cannot remember which page the paragraph came from, do not rely on the explanation.

A quarterly update is a set of figures from your software, not a letter. If you want a sentence to send your bookkeeper, give the tool the totals you have already taken from the software. Do not give it a shoebox and expect a submission.

Draft a short note to my bookkeeper. UK English. Use only these totals. Do not add income or expenses. Do not tell me the update is ready to file.

Quarter: [which]
Software I use: [name]
Income total I am sending: £[amount]
Expense total I am sending: £[amount]
What I am unsure about: [one line, or "nothing"]

You still press send inside the software, or your bookkeeper does, under whatever authority you have given them. The note is not the update.

What this will not decide

It will not tell you that you are under the threshold. It will not tell you that you are exempt. It will not reconstruct a year of cash income you never wrote down. If the records are thin, the fix is the records, starting from today, in software you can export. A tidy paragraph about a missing March does not create the missing March.

If the checker says you should have started in April 2026 and you have not signed up, the next step is the sign-up on GOV.UK, not a better prompt. The sign-up page is linked from the guide at the top of this article.

The UK Trades AI Prompt Pack is free when you sign up to the weekly email: prompts for quotes, chasing payment, tax admin, and customers. Tax admin prompts are for wording and lists. They do not file a return. The signup is on the home page.