As of 13 August 2026, AI can calculate your business mileage.
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 needednone
Who has to check ityou
What the alternative costsThe supplied tool data gives no price for a spreadsheet or mileage service.
If this goes wrong, you may submit an inaccurate expense claim or keep an unreliable record for your accounts and tax return.
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, no skill needed, and roughly 30 minutes until you can act on the result.
How to actually do it
- Open your mileage log, calendar and expense records, and collect each journey's date, start point, destination, business purpose and whether the distance is one way or return.
- Add the distance for each journey from your existing log or a map, keeping the unit consistent and marking any distance you cannot confirm.
- Paste the records and the approved reimbursement rate, if one is stated in your employer's policy, into the prompt.
- Ask the model to list missing, duplicated and ambiguous journeys before it calculates the totals.
- Answer its questions from your calendar, employer policy and map results, then ask it to produce the completed table and totals.
- Compare every distance with the route shown in your map, remove ordinary commuting unless your policy and circumstances support including it, and check the arithmetic against the total.
- Send the checked table to the person who approves your expenses, or to your accountant if it will support accounts or a tax return.
Prompt
Calculate my UK business mileage from the journey records below. Treat each row as one journey unless I state that it is a return journey. Do not invent missing distances, dates, locations, purposes or rates. First identify missing, duplicated or ambiguous rows and ask me about them. Then produce a table with date, start, destination, business purpose, one-way or return status, distance used, and calculation. Give totals by month and for the whole period. If I provide an approved reimbursement rate, calculate the amount using that rate; otherwise report mileage only and do not guess a rate. Keep business travel separate from ordinary home-to-work commuting unless I explicitly identify a journey as allowable business travel. Show the arithmetic clearly so I can compare each distance with a map and each purpose with my employer's expense policy. Do not give tax advice. State that the result is not professional advice and flag any issue an accountant should check. Journey records: [paste your records here]. Approved mileage rate, if known: [paste the rate and its source here].
Open it prefilled in ChatGPT or Claude, or copy it into Gemini, which takes no prefill link.
What it gets wrong
- AI cannot know whether an unusual journey qualifies as business travel under your employer's policy or the relevant tax rules.
- AI cannot confirm that your locations and distances reflect the route you actually drove.
- AI cannot establish an approved reimbursement rate when you have not supplied one.
- AI cannot take responsibility for the accuracy of the expense claim or tax record.
- AI cannot replace an accountant when the mileage forms part of a serious or disputed tax matter.
Even on a YES, the friction has a name: legal accountability, verification cost and judgement under ambiguity.
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 | 2 |
| Verification | 1 |
| Liability | 1 |
| Effort delta | 2 |
| Total | 8 / 10 |
The methodology and its thresholds are published in full.
FAQ
- Can AI work out my business mileage?
- Yes, if you provide the journeys and either their distances or enough location detail to check them. It can total the mileage and apply a rate you provide, but it cannot decide every disputed business-travel question for you.
- Can ChatGPT calculate mileage reimbursement?
- Yes, when you give it the mileage and the approved rate. Do not let it guess a rate, and compare the result with your employer's expense policy before submitting it.
- Can I use AI to calculate mileage for HMRC?
- You can use AI to organise and total your records, but the claim remains your responsibility. This is not professional advice, and an accountant should check a serious, unusual or disputed tax matter.
- How do I check AI-calculated business mileage?
- Compare each route with a map, check the date and purpose against your calendar, and recalculate the totals from the table. Then check that the journeys meet your employer's policy before sending the claim.
Nearby answers
- Can AI calculate my business travel expenses?YES
- Can AI calculate my HMRC mileage allowance?YES
- Can AI calculate my expense totals?YES
- Can AI check if I can reclaim VAT on an expense?PARTLY
- Can AI check which of my business expenses are tax deductible?PARTLY
- Can AI choose a business expenses app for me?YES
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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