A mileage log is a record of business journeys made in a personal vehicle. It is the primary evidence used to support claims for mileage allowance payments (MAPs) and tax-deductible travel expenses. Without a proper mileage log, HMRC can disallow claims during a compliance check, resulting in additional tax, interest and potentially penalties.
Whether you are a sole trader claiming business mileage against your profits or an employee claiming tax relief on unreimbursed business travel, the principles of good mileage record-keeping are the same.
HMRC approved mileage rates
HMRC sets Approved Mileage Allowance Payments (AMAPs) that employers can pay tax-free to employees who use their own vehicle for business travel. The same rates are used by sole traders to claim a deduction against trading profits.
| Vehicle type | First 10,000 miles per tax year | Each mile over 10,000 |
|---|---|---|
| Car or van | 55p | 25p |
| Motorcycle | 24p | 24p |
| Bicycle | 20p | 20p |
These rates are designed to cover all running costs of the vehicle, including fuel, insurance, servicing, depreciation and road tax. If you claim using the AMAP rates, you cannot also claim separately for these costs.
For a broader view of claimable travel costs, see our guide to mileage allowance and tax-deductible expenses.
What HMRC requires in a mileage log
HMRC does not prescribe a specific format, but the log must contain sufficient detail to demonstrate that each journey was made for a legitimate business purpose. The essential information for each journey is:
| Field | Detail required |
|---|---|
| Date | The date the journey was made |
| Start location | Where the journey began |
| Destination | Where the journey ended |
| Purpose | The business reason for the journey |
| Miles | The distance in miles (one way or round trip, stated clearly) |
| Vehicle used | If multiple vehicles are used |
Example mileage log entries
| Date | From | To | Business purpose | Miles |
|---|---|---|---|---|
| 8 Jan | Office, Manchester | Client site, Leeds | Quarterly review meeting | 88 |
| 12 Jan | Home, Manchester | Supplier, Sheffield | Stock purchasing visit | 76 |
| 15 Jan | Office, Manchester | HMRC office, Salford | VAT compliance meeting | 12 |
| 22 Jan | Home, Manchester | Conference, Birmingham | Industry conference | 172 |
| 28 Jan | Office, Manchester | Client site, Liverpool | Project kickoff meeting | 70 |
Business travel vs commuting
One of the most important distinctions in mileage claims is between business travel (allowable) and commuting (not allowable).
| Journey type | Tax treatment |
|---|---|
| Home to permanent workplace | Commuting – not claimable |
| Permanent workplace to client site | Business travel – claimable |
| Home to temporary workplace (under 24 months) | Business travel – claimable |
| Travel between two business locations | Business travel – claimable |
| Home to regular place of work on a day when also visiting a client | Only the excess over the normal commute may be claimable |
Sole traders who work from home have no commute, so journeys from home to meet clients or suppliers are generally treated as business travel. However, if a sole trader has a separate business premises that they attend regularly, travel between home and that premises is commuting.
Temporary workplaces
An employee or sole trader working at a temporary workplace can claim mileage for travel from home to that workplace. A workplace is temporary if:
- The worker attends it for a limited period or for a temporary purpose
- The period of attendance does not exceed, and is not expected to exceed, 24 months
Once it becomes clear that attendance will exceed 24 months, the workplace is treated as permanent from that point forward.
Sole traders: mileage or actual costs
Sole traders can choose between two methods for claiming vehicle expenses:
Method 1: AMAP rates (simplified)
Claim the approved mileage rates for each business mile: since 6 April 2026, 55p for the first 10,000 and 25p thereafter. This is the simpler method and requires a mileage log.
Method 2: Actual costs (proportional)
Claim a proportion of the actual running costs (fuel, insurance, repairs, servicing, road tax, finance interest) based on the ratio of business miles to total miles driven.
| Item | Annual cost | Business proportion (60%) | Claimable |
|---|---|---|---|
| Fuel | £2,400 | 60% | £1,440 |
| Insurance | £600 | 60% | £360 |
| Servicing and repairs | £800 | 60% | £480 |
| Road tax | £180 | 60% | £108 |
| Total | £3,980 | £2,388 |
Under the actual costs method, the mileage log must record all journeys (business and personal) to calculate the business proportion accurately.
Once a method is chosen for a particular vehicle, you must continue to use the same method for as long as you use that vehicle in the business. You can choose a different method for a replacement vehicle.
Employees: claiming mileage
If an employer pays employees at the AMAP rates, there is no tax or National Insurance to pay on the reimbursement. If the employer pays less than the AMAP rates, the employee can claim Mileage Allowance Relief (MAR) for the difference through Self Assessment or by contacting HMRC. If the employer pays more than the AMAP rates, the excess is treated as earnings subject to income tax and National Insurance.
Keeping a compliant mileage log
HMRC accepts mileage logs in any format – spreadsheets, notebooks, smartphone apps or records within accounting software. The format does not matter provided the information is complete and accurate.
Mileage logs must be retained for 5 years after the 31 January Self Assessment deadline (sole traders), 6 years from the end of the accounting period (limited companies) or 4 years after the end of the tax year (employees).
Common mistakes
- Not recording journeys at the time – trying to reconstruct a log weeks later from memory is unreliable and unlikely to withstand HMRC scrutiny
- Claiming commuting miles – journeys between home and a permanent workplace are never business travel
- Rounding or estimating distances – HMRC expects actual distances; use a route planner for accuracy
- Mixing AMAP rates and actual costs – once a method is chosen for a vehicle, it applies to all business journeys in that vehicle
- Failing to distinguish business and personal miles – under the actual costs method, total mileage must be recorded to calculate the business proportion