Window fitter invoice template: fit-only work, CIS and VAT
Most window fitters are paid per window or per door by the company that sold the job, while some sell and fit direct to homeowners. The invoice is simple until you hit remakes, extra making good and the VAT question every installer gets asked: is double glazing zero rated? (It isn't.) Here's a layout with a checked example.
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Window fitter rates
Checkatrade's trade cost table (updated October 2026) lists window fitters at £200 to £400 a day, or about £25 to £50 an hour. That's what homeowners pay. Fit-only work for a window company is more often paid per unit (a price per window, door or bay), sometimes with a day rate for extras. Write the price list into your agreement with the company so each invoice can be checked against it, and compare it with your day rate using the day rate calculator.
What goes on a window fitter's invoice
- The job reference and address from the window company's order, so they can match it.
- One line per unit type: windows, doors, bays, with the quantity and the per-unit price.
- Extras, such as extra making good to reveals, cutting out rotten timber, or a second visit because the frame was wrong. Say who agreed it.
- Remakes: if a unit was made to the wrong size, a return visit to fit the remake is usually chargeable to the company, not the homeowner. Agree that in advance.
- Materials you bought, such as foam, sealant and packers, on a separate line.
- The certificate reference, if relevant. Replacement windows in England and Wales normally need either building control sign-off or a competent person scheme certificate, such as FENSA. Putting the reference on the invoice saves questions later.
CIS: fit-only for a window company
CIS 340 lists the installation of and repair to glazing, windows and doors as construction work. Making and delivering the windows is outside CIS, but HMRC's manual CISR14220 says a contract to supply and fix is within it. That gives three common cases:
- You fit for a window company that sold the windows fitted. The company's business includes construction work and it's paying you, so it's normally a contractor and deducts CIS from your labour, even though its customer is a homeowner.
- You fit for a builder: CIS applies in the normal way.
- You sell and fit direct to a homeowner: no CIS, because a householder isn't a contractor.
Fitting solar, blackout or anti-shatter film to glass is listed as excluded from CIS. If you're unsure how a particular customer or job is treated, check with HMRC or your accountant before invoicing.
Worked example: fit-only for a window company
Ryan fits windows and a front door for a window company that sold them fitted to a homeowner. He is CIS registered (20%) and not VAT registered. The prices are illustrations, not market figures.
| Line | Qty | Rate | Amount |
|---|---|---|---|
| Fit uPVC windows, order W-5520, 22 Park Lane (labour) | 6 | £85.00 | £510.00 |
| Fit composite front door (labour) | 1 | £150.00 | £150.00 |
| Extra making good to reveals, agreed with office 16 Oct (labour) | 0.5 day | £240.00 | £120.00 |
| Foam, sealant and packers bought by Ryan (materials, receipt attached) | 1 | £38.90 | £38.90 |
| Total | £818.90 |
| Labour subject to CIS | £780.00 |
| CIS deduction at 20% | £156.00 |
| Paid to Ryan | £662.90 |
Check: 6 × £85 = £510, plus £150 and £120, makes £780 of labour. 20% of £780 is £156. £818.90 − £156.00 = £662.90.
If Ryan were VAT registered and the window company is VAT and CIS registered, this would normally be a reverse charge invoice: no VAT added, the reverse charge wording, and the VAT shown for information (20% of £818.90 = £163.78). The company charges the homeowner VAT as normal.
VAT: double glazing isn't an energy-saving material
Insulation, draught stripping and similar energy-saving materials installed in homes are zero rated until 31 March 2027. Double glazing isn't on that list. VAT Notice 708/6 says secondary or double glazing and low-emissivity glass are standard rated. So a VAT-registered installer charges 20% on replacement windows for a homeowner. Draught stripping fitted on its own can qualify for 0%. If it comes as part of a window installation, it's likely to be part of one standard-rated supply, so check the notice or with your accountant before zero rating any of it.
For manufacturers who also install, HMRC's reverse charge guide has a 5% disregard: if the construction services are 5% or less of the total contract value, the reverse charge doesn't apply to the contract. It's judged on the whole contract value, agreed at the start.
Common mistakes
- Telling a homeowner double glazing is zero rated. It's standard rated.
- Assuming a window company can't deduct CIS because the end customer is a homeowner.
- Fitting a remake without agreeing who pays for the return visit.
- No order number on the invoice, so the company can't match it.
- Leaving off the certificate reference, then being chased for it months later.
Free window fitter invoice template
For fit-only work, download the free CIS invoice template (PDF or Excel) and add a row per unit type. For direct homeowner jobs, use the general invoice template (PDF, Word or Excel), and the free quote generator for the price (with an account, you can save the quote and later turn it into the invoice). Neither template is window-specific. See the sample invoice for a finished layout. If CIS is taken off your pay, the CIS refund checker gives a quick estimate (not tax advice) of whether you may be due money back.
Related trade guides
Window work often sits alongside the joiner (timber windows and doors), the bricklayer (openings) and the plasterer (making good). See all trade invoicing guides.
Free: The UK Contractor's Cheat Sheet 2026/27
CIS rates, overtime maths, tax dates, mileage, VAT and late payment, on 2 pages. Keep it on your phone or print it for the van.
Frequently asked questions
Is double glazing zero rated for VAT?
No. VAT Notice 708/6 says secondary or double glazing and low-emissivity glass are standard rated. They aren't energy-saving materials for the 0% rate.
Does CIS apply to fitting windows?
Yes when you work for a contractor, including a window company that pays you to fit windows it has sold. There's no CIS on work directly for a homeowner.
Who pays for fitting a remake?
Whoever your agreement says. Usually the window company, because it ordered the wrong size. Agree it in writing before you go back.
Should I put the FENSA number on the invoice?
It's not a legal requirement for the invoice, but adding the certificate reference helps the customer and saves questions later.
Sources
- VAT Notice 708/6: energy-saving materials and heating equipment – GOV.UK
- CIS 340: guide for contractors and subcontractors (Appendix C) – GOV.UK
- Construction Industry Scheme manual CISR14220: manufacture, delivery and supply and fix – HMRC
- VAT reverse charge technical guide (5% disregard) – GOV.UK
- How much do tradespeople cost in the UK in 2026? (window fitter rates, updated October 2026) – Checkatrade
This guide is general information, not legal, tax or financial advice. Rules and rates change, so check the linked GOV.UK pages for the current position.