Vehicle costs are among the most common expenses claimed by UK sole traders and small business owners — and among the most frequently queried by HMRC. Whether you drive a van between building sites in Leeds, visit clients across London in your own car, or courier goods around Birmingham on a moped, the tax rules around business travel are worth understanding properly. Claim too little and you leave money on the table. Claim too much — or without proper records — and you risk a compliance check. This guide cuts through the confusion and gives you a clear, practical framework for claiming what you are genuinely entitled to.
The Two Methods: Mileage Rate vs Actual Costs
The first decision you need to make is which calculation method to use. HMRC offers two approaches, and the one that suits you depends on how you trade and how you use your vehicle.
The flat-rate mileage method — formally known as Approved Mileage Allowance Payments (AMAP) — lets you claim a fixed pence-per-mile rate that covers fuel, oil, tyres, servicing, insurance, and depreciation all in one. For the 2024/25 tax year the rates are:
- Cars and goods vehicles: 45p per mile for the first 10,000 business miles; 25p per mile above that threshold
- Motorcycles: 24p per mile
- Bicycles: 20p per mile
So if you drive 12,000 business miles in a year, your deductible amount is (10,000 × 45p) + (2,000 × 25p) = £4,500 + £500 = £5,000. Simple and straightforward.
The actual costs method requires you to record every vehicle expense — fuel receipts, insurance premiums, road tax, MOT, servicing, and a capital allowance claim for the vehicle's purchase price — then apportion the business-use percentage based on your total mileage. If you drive 15,000 miles a year and 9,000 of those are for business, your business-use proportion is 60%, and you can claim 60% of your total vehicle running costs.
The flat-rate method is simpler and often more tax-efficient for lower-mileage drivers or those with fuel-efficient vehicles. The actual costs method can yield a larger deduction for high-mileage drivers with expensive-to-run vehicles. Crucially, once you have chosen the flat-rate method for a particular vehicle, you must stick with it for the life of that vehicle — you cannot switch mid-ownership.
What Counts as a Business Journey?
This is where many business owners make costly mistakes. HMRC is precise about what qualifies as a business journey, and the distinction matters enormously.
A business journey is travel that is wholly and exclusively for the purpose of your trade. Visiting a client, travelling to a temporary workplace, attending a trade exhibition, or collecting stock from a supplier all qualify. If you are a plumber travelling from your home to a customer's property in Sheffield, that journey is deductible.
What does not qualify is ordinary commuting — travelling from your home to a fixed, permanent place of work. Even if you are self-employed, HMRC does not allow a deduction for travel between your home and a regular base. The one important exception is if your home is your base of business (for example, a sole trader who genuinely works from home and travels out to clients) — in that case, all client-facing travel from home is a legitimate business journey.
Mixed journeys — say, dropping your child at school on the way to a client meeting — are also disallowable unless the private element is genuinely incidental. When in doubt, keep the journey separate.
Keeping Records That Will Satisfy HMRC
Good record-keeping is not optional — it is the difference between a valid claim and a disallowed one. HMRC can enquire into your Self Assessment return up to four years after the filing date (longer if it suspects deliberate inaccuracy), so your records need to be durable and detailed.
Your mileage log should record, for each journey:
- The date of travel
- The start and end locations (e.g. "Home, Manchester M4 → Client site, Salford M50")
- The business purpose (e.g. "Site survey for J. Brennan kitchen renovation")
- The odometer reading at the start and end, or the distance covered
A notebook works, but a spreadsheet or dedicated app is far more practical — especially if you are logging dozens of journeys a week. Platforms like BizHub365 allow you to log mileage directly against a client record, so your travel is automatically linked to the relevant customer or project. When tax time arrives, the totals are ready to pull into your accounts without digging through scraps of paper.
Retain fuel receipts too, even if you are using the flat-rate mileage method — if you are VAT-registered, you may still be able to reclaim input VAT on fuel using HMRC's advisory fuel rates (a separate calculation to the AMAP rates).
VAT, Limited Companies, and Additional Considerations
If you trade through a limited company, the rules differ slightly. The company itself cannot use the AMAP flat rates in the same way as a sole trader; instead, it can reimburse an employee-director for business mileage using the AMAP rates tax-free. The company then deducts the reimbursement as a business expense. Any reimbursement above the AMAP rates becomes a taxable benefit and must be reported on a P11D — or handled through a PAYE Settlement Agreement.
VAT-registered businesses should also be aware of HMRC's advisory fuel rates, updated quarterly, which allow you to reclaim the VAT element on fuel for business journeys. For example, if HMRC's advisory rate for a 1.6-litre petrol car is 14p per mile, you can treat 2.33p of that as reclaimable VAT (14p ÷ 6). The arithmetic is fiddly, but worthwhile for high-mileage businesses.
Electric vehicles add another layer of complexity. There is currently no AMAP-equivalent rate for company-owned electric cars; however, HMRC does publish an Advisory Electricity Rate (AER) — currently 9p per mile — for employees charging a company electric vehicle. If you drive a personally owned electric vehicle for business, you can still use the standard 45p/25p AMAP rate, which covers charging costs.
Avoiding the Most Common Mistakes
Even experienced business owners trip up on vehicle expenses. Here are the pitfalls worth watching for:
- Claiming commuting as business travel. As noted above, this is HMRC's most frequently identified error in mileage claims.
- Switching methods mid-vehicle. Once you elect to use the flat-rate mileage method for a car, you cannot switch to actual costs while you own the same vehicle.
- Forgetting the 10,000-mile threshold. The rate drops from 45p to 25p above 10,000 miles per tax year — many business owners accidentally claim 45p throughout.
- Reconstructing mileage logs at year-end. HMRC expects contemporaneous records. A log written retrospectively in January for the entire prior year is unlikely to be accepted during an enquiry.
- Claiming 100% business use for a vehicle that is also used privately. Unless the vehicle is demonstrably unavailable for private use (such as a panel van with no rear seats kept at business premises overnight), HMRC will challenge a 100% business-use claim for a car.
Putting It All Together
Claiming business mileage and vehicle expenses correctly is one of the most effective ways to reduce your tax bill as a UK sole trader or small business owner — but it rewards those who are methodical about record-keeping from day one. Choose the right method for your circumstances, log every journey at the time it happens, and understand the boundaries between business travel and private use.
If you find yourself juggling mileage logs, fuel receipts, and quarterly VAT returns all at once, a platform like BizHub365 can bring your mileage tracking, expense recording, VAT submissions, and Self Assessment figures into one place — reducing both the admin burden and the risk of errors. Visit bizhub365.co.uk to see how it works for sole traders and small businesses across the UK.
When in doubt about a specific vehicle arrangement — particularly around company cars, benefit-in-kind calculations, or electric vehicle charging — it is always worth speaking to a qualified accountant. The relief is generous; you just need to claim it correctly.