UK Mileage Calculator
Use this tool to estimate your HMRC-approved mileage amount, compare it with what your employer pays, and estimate possible tax relief on any shortfall.
How this mileage calculator UK page helps
If you drive for work, mileage can quietly become one of your biggest annual expenses. This calculator gives you a practical way to estimate what your trip is worth under UK mileage rules and whether you may be able to claim additional tax relief.
It is useful for:
- Employees using their own car for work travel
- Managers approving expense claims
- Freelancers and sole traders comparing methods
- Anyone who wants clearer records before tax season
Current HMRC mileage rates (common reference)
The calculator is based on widely used Approved Mileage Allowance Payments (AMAP) references:
- Car/van: 45p per mile for first 10,000 business miles in a tax year, then 25p
- Motorcycle: 24p per mile
- Bicycle: 20p per mile
Rates can change, so always confirm with official HMRC guidance before filing or submitting final claims.
What counts as business mileage in the UK?
Business mileage usually means travel that is wholly for business purposes. Typical valid examples include:
- Driving from your normal workplace to a client site
- Travel between temporary workplaces
- Trips to meetings, training, and business-related site visits
Commuting between home and your regular workplace is generally not business mileage. This is one of the most common mistakes in claims.
How to use the calculator correctly
1) Choose your vehicle type
Pick car/van, motorcycle, bicycle, or a custom rate if your policy differs internally.
2) Enter miles for this claim period
This can be one trip, one week, one month, or any period you track.
3) Add miles already claimed this tax year
This matters most for car/van claims because crossing 10,000 miles changes the approved rate from 45p to 25p.
4) Add employer reimbursement rate (optional)
If your employer pays less than HMRC’s approved amount, you may be able to claim Mileage Allowance Relief on the shortfall.
5) Select your tax band
The calculator estimates potential relief by multiplying shortfall by your tax rate.
Example scenarios
Employee reimbursed below HMRC approved amount
You travel 4,000 business miles in the year and your employer pays 30p/mile. HMRC approved amount at 45p is higher, leaving a shortfall. You may claim tax relief on that gap rather than receiving the full gap as cash.
High-mileage employee over 10,000 miles
If you have already claimed 9,800 miles and now submit 500 more, only 200 miles are calculated at 45p; the remaining 300 are at 25p. Tracking cumulative mileage is essential.
Self-employed perspective
If you’re self-employed and using simplified expenses, mileage rates are typically used as a deduction method. Your final tax impact depends on your overall business accounts and allowable expenses.
Record keeping checklist
Keep records strong and simple:
- Date of each journey
- Start and end locations
- Business purpose of the trip
- Miles travelled
- Total business miles to date in tax year
A clear mileage log protects you if figures are ever questioned and makes year-end reporting faster.
Common mileage claim mistakes to avoid
- Including normal home-to-office commuting as business mileage
- Forgetting to track annual total and missing the 10,000-mile threshold effect
- Assuming tax relief equals full shortfall value
- Not retaining supporting evidence (calendar entries, meeting notes, route logs)
Final thoughts
A mileage calculator won’t replace professional tax advice, but it will dramatically improve your accuracy and confidence. Use it monthly, keep evidence tidy, and verify rates when tax rules update. Small habits here can prevent expensive corrections later.