Two rounds, same money. One cleaner has 250 customers at £10. The other has 125 at £20. Both take about £2,500 a cycle. One of them drives twice as far to get it, knocks twice as many doors, and has twice as many people who might move house in March.
That is most of the argument about window cleaning business numbers in one paragraph. A one person window cleaning business does not need a dashboard. It needs about six numbers, and it needs permission to stop counting the rest.
The short list a one person window cleaning business runs on
Six things, in the order they move money. Five are numbers. The sixth is a filing habit that keeps the other five defensible.
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Round value, not customer count. It is what every job on the round is worth at the booked price, added up once over one full cycle, not once per calendar month. On a four-weekly round you go round thirteen times a year, not twelve, so the two are different figures. Count cycle value straight off the round; where this post says monthly, that is cycle value × your own cleans a year ÷ 12, so × 13 ÷ 12 on a four-weekly round and less than that on a longer one. Customer count is the vanity number. It goes up when you take on scattered £8 jobs at the far end of town, which makes the business worse, not better.
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Daily takings. Not weekly, not monthly. Daily, because that is the unit you actually work in. Self employed window cleaner earnings in the UK cluster at £150 to £250 a day, which is takings rather than profit. A supplier's own guidance puts a full day at 15 to 20 domestic properties for one person on a water-fed pole with a compact round. Turning over £120 on a dry Tuesday with no van trouble is rarely an effort problem. It is route order, or it is what you charge per house.
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Cycle adherence. Whether you are still going round every four weeks, or have slipped to five and not admitted it. Almost nobody tracks it, and it moves more money than the rest of the list put together. It gets its own section below.
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Who owes what, and since when. The total is close to useless; the ageing is the thing. Forty pounds outstanding is fine if it is four cleans from last week and alarming if it is one customer since April. Most cleaners work to the same rule, two cleans unpaid and you stop. Whatever version of it you settle on, you cannot apply it unless you know who is on their second.
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Customers gained and lost each month, as one net figure. Nine on, five off, so 9 - 5 = plus four. Written down monthly, it tells you whether canvassing is keeping up with churn or whether you are running to stand still while telling yourself the round grows.
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Receipts, numbered and in date order. The habit rather than the number. Deeply unglamorous, and the thing that saves you in January when you are trying to remember what the £212 to the motor factor in November was for.
Cycle adherence is the number that quietly sets your income
Take 200 customers at an average of about £11 a clean. Four-weekly is 52 ÷ 4 = 13 cleans a year. Six-weekly is 52 ÷ 6 = 8.7.
| Cycle | Cleans a year | 200 customers are worth |
|---|---|---|
| 4-weekly | 13 | about £28,600 |
| 6-weekly | 8.7 | about £19,100 |
Scale it to your own book
Per customer that is 13 × £11 = £143 a year on four weeks, against 8.7 × £11 = £95.70 on six. Multiply by your own count.
The slip is self-feeding, too. Glass left longer is slower to clean, so the days run over, and the next gap stretches again. The mechanics are in how the frequencies compare.
Track it crudely. Date last done against date due, counted once a month. If a quarter of the round is running a week late, you have your answer.
The longer list, and why each one eats an evening
This is the half nobody writes down.
Stop these tonight
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Customer headcount as a headline. It is the number cleaners quote each other in the pub. "I'm on 380." On 380 what, at what price, on what cycle. The other two matter more.
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Per-job time and motion. Timing every house to the minute makes a lovely spreadsheet and changes nothing. You already know which jobs are slow: the awkward conservatory, the one with the gravel drive and no outside tap. Reprice them at the next rise instead.
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Exact odometer readings at every stop. Keep a running note of business miles by day or by week, in a form you could show someone, and stop there. Forecourt-by-forecourt precision is not what saves you tax. HMRC's flat rate, a fixed pence-per-mile you claim instead of itemising fuel, tax, insurance and servicing, means the miles are the only thing you have to record.
Hourly rates and comment cards
Obsessive hourly rate calculation. The trade forums have been sceptical for years about the £30-an-hour figures that get posted, and not because anyone is lying. The good hour gets remembered and the drive between areas does not, so one strong morning becomes the figure someone quotes for the year. One cleaner of 18 years said plainly he had never come close to the numbers he saw posted. Work your rate out once, price from it, then leave it alone. Recalculating weekly is a mood, not a measurement.
Comment cards and feedback slips. The trade view is blunt: they invite complaints you would never otherwise hear about. Hand a card to a happy customer and you have asked them to go looking for something wrong. The fair counter is that a customer with a real grumble and no way to raise it goes quiet, then cancels. Both are true. Most cleaners settle it by asking the two or three people whose opinion they want, at the door.
What a round is worth, if you are buying or selling
For anyone at that stage; if not, the six above are the post.
Window cleaning round value is the question everybody asks, and the answers genuinely conflict. Use 3 to 5 times the monthly figure, monthly as converted in point 1, not one cycle's takings. That range comes from cleaners who have bought and sold rounds: one documented sale went at £3,200 a month for £16,000, and £16,000 ÷ £3,200 = 5 times. Buyer-side advice goes lower still: above 3 or 4 is hard to defend for a list of names with no obligation to stay. Recent trade marketing content quotes 8 to 12 times monthly, a much nicer number, and not from people who have sat at a kitchen table and bought a round. Price on the 3 to 5.
Expect to lose around 5% of customers in the handover, with 5% to 10% the tolerance negotiated into the deal. The usual protections:
- staged payment, a deposit with the balance after the first full cycle
- a written contract rather than a handshake
- the seller walking the round with you, door by door
- a clause stopping the seller contacting those customers for three to six months
And a documented round with a named, contactable customer list fetches materially more than the same work carried in a paper book, purely because a buyer can see a history. Reason enough to get the round off a spreadsheet years before you need to.
Running costs for one van and one person
For anyone wondering whether their own outgoings are normal. With one van, annual expenses land between £3,400 and £9,100 all in, wide because it covers fuel through to a new hose. Pure water is the bit people underestimate. DI resin, the deionising media in the vessel that strips the last minerals out of your water, runs £25 to £40 a vessel and lasts two to four weeks if you are busy, and it swings hugely with local water hardness.
Public liability insurance is cheap now, with real annual quotes spanning £117 to £710. One insurer reports that around three quarters of the window cleaners on its books take £1m of cover, which is what people buy, not advice on what you need, so check what any commercial work you want asks for. Two things to do. Read the height clause before you agree to a townhouse, because plenty of policies exclude work above 5 metres. And take out employers' liability insurance, which stops being optional the moment anybody works for you, even a lad on Saturdays.
Tax thresholds, and which one you hit first
For anyone close to one of the lines below. I am not an accountant. Check it against your own position.
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VAT. The threshold is £90,000 of taxable turnover on a rolling 12-month basis. For a domestic-only round that is a ceiling, not a milestone, because your customers cannot reclaim VAT. Crossing it means absorbing 20% yourself or asking Mrs Patel to pay £15 × 1.2 = £18 for the same clean. It is the exact reason a lot of cleaners stop at one van.
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Mileage, the flat rate from the note above. For 2026-27 it is 55p a mile for the first 10,000 business miles and 25p after that, up from 45p on 6 April 2026. It already covers fuel, insurance, tax and servicing, so none of those go on top. And you cannot use it on a vehicle you have claimed capital allowances on, that is, written part of the van's purchase price off against your profit rather than only claiming what it costs to run. If your accountant did that when you bought the van, the flat rate is closed to you on it.
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Making Tax Digital for Income Tax, in stages: over £50,000 from April 2026, over £30,000 from April 2027, over £20,000 from April 2028. A round worth £2,000 a month, monthly as converted in point 1 rather than £2,000 a cycle, is £2,000 × 12 = £24,000 a year, over the £20,000 line, so you are in the 2028 group. Sounds distant. It is two price rises away.
Six numbers that keep themselves
Round value. Daily takings. Cycle adherence. Who owes what and since when. Net on and off each month. And the receipt file behind them.
Most of the short list falls out of the round itself, as long as the round sits somewhere that records what happened: what was cleaned, when, at what price, and who has paid. RoundWiz keeps the record they come off, and the adding up is still yours. The owing list is already there on a Sunday night, and the prices and frequencies are in one place to add up, rather than scattered across eleven months of columns.
£7.99 a month, or £79.90 for the year, VAT included. One flat price whatever the round is worth, so the bill does not grow as the book does. There are thirty days free at the front of it, no card asked for, and it will take the spreadsheet you already have.