As of 13 August 2026, AI can only partly file your P11D(b) form.

What to actually do

1. Hand it to a person

   The route this page recommends

   Someone with a licence or accountable authority has to sign this before it counts.

2. Use a tool built for this

   Second choice

3. Do it yourself

   The distant third

   A chat interface, chat-fluent skill, and roughly 1 hour until you can act on the result.

   How to actually do it

   1. Open the GOV.UK guidance for P11D and Class 1A National Insurance and save the current instructions and filing route for the employer.
   2. Gather the employer reference, payroll reports, benefits records, P11D forms or equivalent employee schedules, invoices, payment records and details of any benefits processed through payroll.
   3. Paste the records and the relevant GOV.UK guidance into the prompt, removing unnecessary personal data and labelling the tax year and each source document.
   4. Ask the chatbot to build the benefit-by-benefit schedule, show the source of every figure and list missing records or uncertain treatments without filling gaps.
   5. Have the payroll lead or accountant compare each drafted figure and classification with the payroll ledger, benefit records and GOV.UK instructions, and resolve every flagged item.
   6. Enter the verified figures into the employer's HMRC-approved filing route, or send the checked schedule to the accountant or payroll provider responsible for submission.
   7. Save the submitted return, confirmation, supporting records and payment details with the employer's tax records.

   Prompt

   You are helping me prepare, not file, a UK employer P11D(b) return. Use only the records and official GOV.UK guidance I provide. Do not invent or estimate any amount, benefit, employee, deadline or National Insurance treatment. First list every input needed and identify anything missing. Then create a draft working schedule with one row per benefit and the source record for each figure. Separately flag any item that needs an accountant, payroll specialist or HMRC confirmation, including benefits with unusual valuation, shared or private use, payrolled benefits, terminated arrangements or uncertain Class 1A National Insurance treatment. Do not decide disputed tax treatment. Reconcile the totals to the payroll and benefits records, show the arithmetic, and produce a final checklist for a responsible employer to verify before entering the figures into the approved HMRC filing route. State clearly that this draft is not a submission and that the employer remains responsible. Here are the records and guidance: [paste records and official GOV.UK links or text]

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