Tax Guide for Window Cleaners: Expenses and Record Keeping

The Accounted Business Team·27 January 2026·7 min read

Keeping Your Tax Affairs Crystal Clear

Window cleaning is one of those trades where you can start with a bucket and a squeegee and build a serious business. But whether you are a sole trader with a residential round or running a team with a water-fed pole system and a van, you have the same tax obligations: register with HMRC, keep records, claim your expenses, and file a Self Assessment return.

This guide covers everything a self-employed window cleaner needs to know about tax for the 2025/26 tax year.

Registering as Self-Employed

You must register with HMRC as self-employed if your income from window cleaning exceeds £1,000 in a tax year. The deadline is 5 October following the end of the tax year you started trading. Once registered, you file a Self Assessment tax return each year.

Most window cleaners operate as sole traders, which is the simplest business structure. You can also set up a limited company, but for most window cleaners the administrative burden of a company outweighs any tax savings unless your profits are consistently above £40,000-£50,000.

Equipment Expenses

Traditional equipment

Basic window cleaning kit is a straightforward business expense. Claimable items include:

Buckets, squeegees, and T-bars
Extension poles and scrapers
Ladders (step ladders and extension ladders)
Chamois leathers and scrim cloths
Cleaning solution and chemicals
Sponges, brushes, and applicators
Safety harnesses and fall-arrest equipment

Water-fed pole (WFP) systems

A water-fed pole system is a significant investment — a good setup can cost £1,000 to £5,000 or more, including the poles, controller, pump, tank, resin vessel, and hoses. This is where capital allowances become important.

Under the cash basis, which most sole traders use, you can claim the full cost of equipment in the year you buy it. So if you spend £3,000 on a WFP system, you deduct £3,000 from your profits in that year.

Under the accrual basis, you would use capital allowances. The Annual Investment Allowance (AIA) of £1 million means you can still deduct the full cost in the year of purchase. Either way, the full cost is claimable — you do not need to spread it over several years.

Replacement parts — new brushes, hose sections, resin, filters — are ordinary revenue expenses and are deductible regardless of which accounting basis you use.

Pure water production

If you produce your own purified water, the cost of the RO (reverse osmosis) or DI (deionisation) system is a capital expense, claimable in the same way as the WFP system. Ongoing costs — replacement resin, filters, membranes, and the water itself — are revenue expenses.

Vehicle Costs

Your van or car is essential to your business. There are two ways to claim vehicle costs.

Mileage rates

Use HMRC's approved mileage rates: 45p per mile for the first 10,000 business miles in the tax year, then 25p per mile after that. This covers fuel, insurance, road tax, MOT, servicing, and depreciation — you cannot claim any of these separately if you use mileage rates.

Keep a mileage log noting the date, route or round, and miles driven for every business journey. Travel from your home to your first job and from your last job back home is claimable if you have no fixed place of work — which most window cleaners do not.

Actual costs

Alternatively, claim the actual running costs of your vehicle, apportioned for business use. If you drive 15,000 miles a year and 12,000 are business miles, you can claim 80% of your fuel, insurance, road tax, MOT, servicing, repairs, and breakdown cover.

If you buy a van or car for business use, you can claim capital allowances on it. Vans qualify for the AIA, so you can deduct the full cost in the year of purchase. Cars are treated differently — they go into a special rate pool (6% writing-down allowance) or main rate pool (18%) depending on CO2 emissions, unless they are electric (100% first-year allowance).

You cannot switch between mileage rates and actual costs for the same vehicle once you have chosen a method.

Water Costs

If you pay for water — whether from a domestic supply for filling your tank or from a commercial water supplier — the cost is a business expense. If you use your home water supply, estimate the business proportion. Some window cleaners install a separate water meter for their business supply, which makes the claim straightforward.

Insurance

Insurance is a necessary cost and is fully deductible:

Public liability insurance — essential if you damage a window, frame, or property
Employers' liability insurance — required by law if you have employees
Vehicle insurance — the business proportion, or included in mileage rates
Equipment insurance — covering theft or damage to your WFP system, ladders, and tools
Personal accident insurance — covers your income if you are injured and cannot work

Buying a Round: Goodwill

Purchasing an existing window cleaning round is common in the industry. You might pay £5,000 to £50,000 for an established customer base, depending on the round's turnover and location.

The purchase price is treated as goodwill for tax purposes. Under the cash basis, you cannot claim goodwill as an expense — it is specifically excluded. Under the accrual basis, goodwill does not qualify for capital allowances either, but you may be able to claim amortisation in your accounts. When you sell the round, any profit above the original cost is taxable.

If you are considering buying a round, it is worth speaking to an accountant about the tax implications, because the treatment depends on your accounting basis and how the purchase is structured.

Cash Record Keeping

Window cleaning is a cash-heavy business, particularly for residential rounds. HMRC knows this, and it is one of the industries they pay close attention to. Poor cash records are one of the biggest risks for window cleaners.

What HMRC expects

You must record every payment you receive, whether cash, bank transfer, cheque, or card payment. For each transaction, note:

The date
The customer name or address
The amount received
The method of payment

Practical tips

Use a round book or app. Record each job as you complete it, noting whether the customer paid and how much. At the end of each day, your round book should reconcile with the cash in your pocket and any electronic payments received.

Bank your cash regularly. Depositing cash into your business bank account creates a verifiable record. If you keep large amounts of cash at home without banking it, you have no independent proof of your income — and HMRC can estimate your earnings if they believe your records are incomplete.

Keep a separate business bank account. This is not a legal requirement for sole traders, but it makes your life enormously easier. Mixing personal and business money in one account is a record-keeping nightmare.

Invoice where possible. Even for residential customers, consider using a simple invoicing or receipt system. An app-generated receipt sent to the customer by text or email creates a digital trail that is much harder to lose than a note in a round book.

What happens if your records are poor

If HMRC opens an enquiry and your records are inadequate, they can issue an assessment based on their own estimate of your income. This often results in a higher tax bill than you would have had with proper records, plus penalties of up to 30% for careless record keeping (or more if HMRC considers the errors deliberate).

Other Deductible Expenses

Phone

The business proportion of your mobile phone bill is deductible. You use your phone for scheduling, communicating with customers, and navigating between jobs.

Clothing

Specialist workwear — such as waterproof trousers, steel-toe boots, and hi-vis jackets — may be claimable if it is not suitable for everyday wear. Branded clothing with your business name is more likely to be accepted. Ordinary clothes are not deductible, even if you only wear them for work.

Marketing

Business cards, flyers, van livery, local advertising, and a simple website are all deductible. Van signwriting is a particularly good investment — it advertises your business every time you drive around your area, and the cost is fully claimable.

Training

Health and safety courses, working at height training, and IPAF or PASMA certification are all deductible.

National Insurance

You pay:

Class 2 NI: £3.45 per week (if profits exceed £12,570)
Class 4 NI: 6% on profits between £12,570 and £50,270, then 2% above that

Both are calculated through Self Assessment.

How Accounted Keeps Your Records Straight

Cash-heavy businesses need bulletproof records, and that is exactly what Accounted provides. Connect your bank account, snap photos of receipts via WhatsApp, and Penny, the AI bookkeeper, categorises everything automatically — fuel, equipment, insurance, and more. Penny also tracks your cash income alongside your bank transactions, so your records are always complete and HMRC-ready.

Start Your Free Trial With Accounted

Do not let poor record keeping put your business at risk. Accounted makes it simple to track every pound in and out, claim all your expenses, and file your Self Assessment with confidence. Start your free trial today.

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