How much tax should a window cleaner set aside? Tax and allowable expenses for 2025/26
A window cleaner's income comes from a round: dozens or hundreds of regular customers paying small amounts, often in cash or by bank transfer. Smaller payments are harder to track, and that is where the tax figure usually goes wrong.
What the tax looks like
Using the 2025/26 rates (England, Wales or Northern Ireland, no other income), a window cleaner with £28,000 of takings and £4,500 of allowable costs has £23,500 of profit and about £2,842 of income tax and Class 4 National Insurance for the year, roughly £237 a month. The figures are an illustration, not an average for the trade. Tax is on profit, not takings.
| Profit for the year | Income tax + Class 4 NI | Per month | Per £1 of profit |
|---|---|---|---|
| £14,000 | £371.80 | £31 | 3p |
| £23,500 | £2,841.80 | £237 | 12p |
| £35,000 | £5,831.80 | £486 | 17p |
Open the calculator already filled in with this example and change the two numbers to yours. It also shows the January and July payment dates.
Costs a window cleaner usually claims
Claim only what you actually spent on the business, and only the business share of anything you also use personally.
- Equipment: ladders, water-fed poles, squeegees, buckets, scrapers. Smaller items are a cost in the year.
- Pure-water systems and fittings, filters and resin.
- Cleaning products and consumables.
- Van or car costs: fuel, insurance, repairs, or the flat mileage rate for the year.
- Insurance: public liability, plus ladder and equipment cover.
- Round-book, app or advertising costs, such as a customer-list app or leaflet drops.
The general list is on GOV.UK: self-employed expenses you can claim, and what you can't. If your costs for the year are under £1,000, the trading allowance may leave you less tax.
Recording a cash and transfer round
You report all your trading income, however it was paid. For a window round the most practical method is to total each day or each round: money collected, paid in cash, by transfer or by card, then match deposits to the round-book at the end of the month. HMRC can ask for the records behind the figures. A deposit of cash into the bank that doesn't match any records is the thing to avoid. Tips are income too. The costs side is easier: most spending is small, regular and the same each month.
VAT
VAT registration starts when taxable turnover for the last 12 months goes over £90,000. A round turning over a fraction of that stays below it.
Records worth keeping
- Tick off the round-book each day and total it weekly.
- Pay cash takings into the business account (or keep a cash log), and note what each deposit covered.
- Keep receipts for equipment and chemicals. A £90 pole kit is easy to forget.
- Log van miles if you use the flat rate, including trips for supplies.
A simple way to total a round-book of regular cash and bank payments by month: the SortedDesk Self Assessment Spreadsheet is a one-off £4.99 download for Excel and Google Sheets. It is a spreadsheet only: nothing here files anything with HMRC, and the sheet doesn't replace an accountant if your case is complicated.
Dates matter too: the 2025/26 return and tax are due on 31 January 2027, and payments on account can make that January bigger than the year's bill.
This is a planning guide, not tax advice. Figures worked with the calculator's 2025/26 rules, and GOV.UK sources read on 21 October 2026: Expenses if you're self-employed, Simplified expenses: vehicles, When to register for VAT.
Try the calculator with this example