United Kingdom: mileage, vehicle expenses and tax records
Simplified mileage or allowable costs
How the local rules work
Eligible self-employed people can use simplified mileage expenses instead of actual vehicle purchase and running costs. Eligibility and prior claims matter.
What to keep
Record business journey dates, purposes and miles. Save costs separately if comparing allowable actual expenses.
What the odometer message means
The app needs total vehicle distance, including personal driving, to estimate business use. Enter beginning and ending odometer readings for the same vehicle and reporting period. Missing total distance means the percentage is incomplete; it does not erase your recorded business trips.
80% business · 20% personal
12,000 ÷ 15,000 × 100 = 80%. Use miles or kilometres consistently. This is a usage ratio, not automatic permission to deduct 80% of every cost.
Avoid this mistake
Do not add fuel, insurance or repairs already covered by simplified mileage. Ordinary home-to-work travel is not an allowable business expense.
Prepare your records in Free Mile Tracker
- Select your country and the correct reporting period.
- Review each trip and distinguish business from personal driving.
- Add dated odometer readings and keep supporting expense documents.
- Export your records and compare them with platform statements before filing.
Official guidance
Source checked October 8, 2026. Confirm the applicable tax year on the official site before filing.