Business mileage records for self-employed people

Business mileage records for a sole trader should identify the journey, date, distance and business purpose. Check whether simplified vehicle expenses are available and suitable before mixing mileage claims with actual running costs for the same vehicle.

Distinguish business travel from private journeys and ordinary travel that does not qualify. Retain the calculation method and evidence supporting any change of vehicle or approach.

Identify the vehicle and the available method

Record the vehicle, ownership arrangement, date it entered business use and any earlier tax treatment. Check whether simplified vehicle expenses are available for that vehicle and business. HMRC sets conditions on using the mileage approach, including interactions with previous claims and continued use of the method. ^[1] A trader should not select mileage for one month and actual running costs for another merely to maximise the result.

Keep the decision with the vehicle record and discuss uncertainty before entering a claim. A limited company, a sole trader and an employee using their own car can have different rules. Establish which situation applies rather than taking a rate from an employee expenses policy. If the vehicle changes during the year, create a separate record and reassess the relevant conditions for the replacement.

Record the purpose as well as the distance

A useful journey entry identifies the date, start and destination, distance and reason for the trip. Describe the client visit, delivery, collection or other business task sufficiently to distinguish it from private travel. A calendar entry saying meeting may not explain whether the journey related to the trade, another employment or a personal appointment.

Use a method that can be maintained reliably: a log, an appropriate app or another consistent record. Check automatically recorded trips before accepting them as business mileage. A route-tracking tool can measure distance but cannot decide whether a journey qualifies for tax purposes. Retain the explanation for unusual routes or combined journeys while the facts are still available, rather than reconstructing them from memory at year end.

Examine regular and mixed-purpose journeys

Travel from home is not automatically business travel simply because the trader stores equipment there or answers emails before leaving. Describe the normal working pattern and locations to the adviser, particularly where there is a regular base or recurring destination. Ask for the relevant tax assessment instead of adopting an assumption based only on where the vehicle was parked overnight.

For a trip with private and business elements, record the actual sequence and purpose. Do not add an unrelated private detour to a business claim without assessment. Keep parking, tolls and other journey costs identifiable, and check how they interact with the chosen vehicle method. The guide to Allowable expense evidence for sole traders helps organise supporting documents without duplicating costs already covered by a simplified calculation.

Reconcile the log with the business activity

Compare a sample of recorded journeys with appointments, delivery records or invoices. Investigate dates with large mileage but no identifiable business task, and days where a known visit has no entry. The aim is an accurate record, not a perfect-looking total. Correct mistakes transparently and retain enough context to explain the final figure.

Where more than one vehicle is used, keep separate totals and identify the relevant driver and arrangement. Avoid combining a business van's journeys with mileage undertaken in another person's car without clarifying the treatment. If several trades use the same vehicle, document the allocation so the same journey is not claimed twice. Use Keeping records for a second business when preparing records across distinct activities.

Review the annual calculation before filing

Check that the mileage total, applicable method and relevant rates correspond to the tax year and vehicle. Do not carry a previous year's spreadsheet formula forward without reviewing its assumptions. Identify any missing period, change of use or earlier claim that could affect the calculation. Keep actual running costs separately where they remain relevant to the accountant's review, even if they are not claimed through that method.

For Self-employed expense review, supply the vehicle history, journey log, proposed calculation and questions about regular or mixed journeys. Ask for a clear decision on eligibility and cost overlap. Preserve that conclusion with the return so a future preparer can see why the method was used and which facts would require reconsideration.

If the recording process has been unreliable, improve it from a clear date and discuss historic gaps honestly. Do not generate fictitious daily journeys to force an estimated annual total into a detailed log. A transparent explanation of available evidence is more useful than a precise-looking record that claims certainty the trader does not possess.

Illustrative scenario

A mobile repairer visits three customer sites and then makes a private detour. Their log identifies the customer journeys separately so the private distance is not silently included in the claim.

Preparation checklist

• Log journeys promptly
• Identify business destinations
• Separate private mileage
• Check the vehicle claim method