Business mileage allowance calculator
If you drive for the work, the flat rate per mile is usually easier than keeping every fuel receipt. Put in your business miles for the year and see the claim.
Business mileage allowance calculator
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The rate drops after 10,000
For cars and goods vehicles the flat rate is 55p a mile for the first 10,000 miles of the tax year and 25p after that. It was 45p before 6 April 2026. Motorcycles are 24p a mile throughout.
Business miles only
Commuting from home to a regular place of work does not count. Trips to clients, to buy supplies and between jobs do. Keep a simple log: date, from, to, miles, why.
It replaces the running costs
The flat rate covers fuel, insurance, repairs and the cost of the vehicle. If you use it for a vehicle you cannot also claim those costs for the same vehicle. It is a choice for the year, so compare it with your real costs.
Figures for the 2026/27 tax year, checked 25 October 2026. Sources: Simplified expenses: vehicles. An estimate, not advice. SideTill is not tax software.
Keep the number for every month
SideTill is the simple record of your side hustle: log the job, send the invoice, record the money when it comes in, and see whether the month actually made you money. It also shows your best month, so you can tell a bad month from a bad habit.
Get SideTill
No account. No sign-up. Your data stays on your phone. The basics are free to use.
Questions
Do I need receipts?
Not for the flat rate, but you need a mileage record. A note on your phone at the end of each job is enough to start.
Does the 10,000 mile switch reset?
Yes, each tax year. Count the miles from 6 April.
Can I use it if I am a limited company?
This is the simplified expenses rule for sole traders. A limited company pays its own employees the approved mileage rates, which is a different calculation.