The test is still “wholly and exclusively” for the trade. If something is mixed use, claim the business share and write down how you split it. You cannot claim the trading allowance of £1,000 and actual expenses in the same year.
Do not put CIS deductions in the expenses column. They belong with tax already paid. Everything else (van, tools, materials, PPE) is a normal sole-trader claim.
What plumbers can usually claim
| Expense | Claimable? | Notes | Keep |
|---|---|---|---|
| Materials used on jobs | Usually yes | Pipes, fittings, boilers you fit. Recharged sales are also turnover. | Merchant accounts, invoices |
| Tools and test equipment | Usually yes | Usually AIA or expenses depending on accounting. | Receipts |
| Van running costs or mileage | Usually yes | Simplified 55p/25p, or actual costs. Not both for the same van. Once you pick mileage for a vehicle, you stick with it. | Mileage log or fuel/insurance invoices |
| PPE, work boots that are protective | Usually yes | Steel toe caps, hard hat, hi-vis. Not a fashion boot. | Receipts |
| Public liability and van insurance (business) | Usually yes | Business policies. A private car policy used as a van is a mess; get the right cover. | Schedules |
| Phone, job-management apps | Usually yes | Business share of the phone. | Bills |
| Waste disposal and permits | Usually yes | Cost of doing the job legally. | Receipts |
| Subcontractors you pay | Usually yes | If you take CIS as a contractor, you have extra duties. Do not ignore that. | Invoices, CIS if you must deduct |
| CIS tax deducted from your invoices | No | Not an expense. It is tax paid on account. Claim it in the tax paid boxes. | CIS statements |
| Ordinary clothes under the overalls | No | Personal. | n/a |
| Fines, ULEZ you could have avoided is still usually allowable as a cost of using the van; penalty charges are not | Sometimes | Congestion/ULEZ charges for business journeys are generally allowable. Penalty notices are not. | Account statements |
| Your own boiler at home | No | Personal, even if you fitted it yourself. | n/a |
Open a printable checklist for this trade.
What you cannot claim
- CIS deductions (they are tax paid, not expenses).
- Everyday clothes.
- Parking tickets and late-filing penalties.
- Drawings (money you pay yourself).
- The family holiday you bolted onto a merchant trip.
Trade-specific traps
- Throwing CIS statements away. You need the total deducted to claim it against the bill.
- Declaring only the amount that hit the bank after CIS.
- Mileage and actual van costs on the same vehicle.
- A “mate’s rates” cash job that never existed on paper, then a van and house HMRC cannot square with the return.
- Paying a labourer cash with no invoice and no CIS when you should have been a contractor.
Records that actually help in this trade
Merchant monthly statements, invoice book, CIS monthly statements, and a job diary that matches the van mileage. Photograph handwritten invoices before they fade in the cab. If you use cash basis, unpaid customer invoices are not income yet. Unpaid merchant bills are not expenses yet either.
Mileage, if you use simplified expenses in 2026/27, is 55p per mile for the first 10,000 business miles, then 25p. That replaced 45p from 6 April 2026. Ordinary commuting is still not claimable. See the mileage guide and home office costs.
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Common questions
Steel toe caps yes, trainers no?
Protective footwear required for the work yes. Ordinary trainers no.
Can I claim a second van?
If it is used in the trade, yes, with a business-use split if it is also personal.