Allowable expenses, van and tool costs, CIS deductions, home-office, VAT and MTD explained for UK self-employed blind, curtain and shutter fitters.
A self-employed blind fitter has one of the cleaner trades to tax on paper and one of the messier ones in practice. You are out in vans, in and out of homes and offices, drilling brackets, hanging made-to-measure roller, Roman, vertical and Venetian blinds, fitting plantation shutters and the occasional awning. The income side is straightforward: you invoice for supply and fit, or labour only. The complications come from where the work sits. Fit directly for a homeowner and it is a plain sole-trader job. Fit as a subcontractor on a builder's project and you are suddenly inside the Construction Industry Scheme with tax already taken off your labour.
This guide covers how your profit is taxed, the specific expenses worth claiming for this trade, how CIS deductions feed into your Self Assessment, National Insurance, VAT and the MTD timetable. Get the van, tools and CIS records straight and the rest follows.
As a sole trader you pay Income Tax on profit, which is everything you invoice for fitting minus your allowable business costs. For 2025/26 the personal allowance covers the first GBP 12,570, then you pay 20% to GBP 50,270, 40% to GBP 125,140 and 45% above, with the personal allowance tapering away between GBP 100,000 and GBP 125,140 to create an effective 60% band. Class 4 National Insurance is 6% on profit between GBP 12,570 and GBP 50,270 and 2% above, with Class 2 NIC settled through Self Assessment, which protects your State Pension record.
Scottish fitters pay Scottish Income Tax through six bands (19%, 20%, 21%, 42%, 45% and a 48% top rate) and carry an S-prefixed tax code, while National Insurance stays UK-wide. Welsh fitters have a C-coded tax code at rates currently matching the rest of the UK. If you also have a PAYE job, or you came off the tools from an employed role mid-year, your code can be wrong; run it through the tax code checker so you are not over or underpaying through the year.
Plenty of fitters start on the side, doing a few jobs at weekends while still employed. The GBP 1,000 trading allowance is built for that. If your gross fitting income for the year is GBP 1,000 or less, it is tax-free and you do not need to register for Self Assessment. Cross GBP 1,000 and you must register and report the full amount.
Above the threshold you get a yearly choice: deduct the flat GBP 1,000 trading allowance instead of working out actual expenses, or deduct your real costs if they are higher. You cannot do both. For a fitter this almost always means claiming actual expenses, because a van, a kit of power tools and insurance comfortably exceed GBP 1,000. The flat allowance only wins in a first part-year where you borrowed tools and barely spent anything.
This is the part that catches blind fitters out. Installing blinds, shutters or awnings as part of the construction, alteration, repair or fit-out of a building counts as construction operations under the Construction Industry Scheme. So when you subcontract to a builder, shopfitter, joiner or main contractor on a project, that contractor must deduct CIS from the labour element of your invoice and pay it to HMRC on your behalf.
The deduction is 20% if you are registered as a CIS subcontractor, or 30% if you are not. It comes off labour only, not the materials you supply (the blinds, brackets and fixings), and not VAT. Register with HMRC so you are deducted at 20% rather than 30%, it makes a real cash-flow difference across a year. Fitting directly for a private homeowner is outside CIS entirely, because a householder is not a contractor.
Because CIS deducts a flat 20% from gross labour before any expenses, most fitters who work through contractors have paid too much tax by the year end. You claim it back: total the CIS deductions from your statements, enter them on your Self Assessment, and they offset your actual Income Tax and Class 4 NIC bill, usually producing a refund. Keep every monthly CIS statement, they are your proof of tax already paid. Our CIS subcontractor guide explains the full mechanics, and the CIS tax calculator estimates the refund you are owed.
An expense is allowable when it is incurred wholly and exclusively for the business. For a fitter the list is dominated by tools, the van and protective gear.
| Expense | What qualifies | Notes |
|---|---|---|
| Power tools | Cordless and SDS drills, drivers, batteries, chargers, multi-tools | Claimed via the Annual Investment Allowance |
| Hand tools and access | Levels, tape measures, screwdrivers, snips, hop-ups, step ladders, work platform | Replaceable consumable tools are everyday running costs |
| Consumables | Drill bits, blades, plugs, screws, brackets, fixings, batteries, sealant | Fully deductible as used |
| Materials and stock | Made-to-measure blinds, shutters, tracks, poles you supply | Deduct against the supply-and-fit income |
| Van running costs | Fuel, insurance, road tax, servicing, MOT, repairs, or simplified mileage | Pick mileage or actual costs and stick with it |
| PPE | Safety goggles, gloves, knee pads, dust mask, branded workwear, safety boots | Protective and branded only, not everyday clothes |
| Insurance | Public liability and tool/van cover | Essential and fully allowable |
| Phone and admin | Business share of mobile, quoting and invoicing software, stationery | Apportion private use out |
| Home-office | Flat-rate or actual share of household costs for quotes, ordering and books | Most fitters do admin from home |
| Professional fees | Accountancy, bookkeeping, trade association membership | Fully deductible |
The van is usually the second-biggest deduction after stock. You have two methods. Simplified mileage pays a flat 45p per business mile for the first 10,000 miles in the year and 25p after that, covering fuel, insurance, servicing, repairs and depreciation in one figure, you just log your business miles between jobs. Or you claim the actual business proportion of every van cost plus capital allowances on the van itself. A fitter racking up heavy daily mileage in a dedicated work van often gets a bigger deduction from actual costs; a lighter-use fitter usually finds mileage simpler and just as good. You must keep to one method per vehicle once you choose it. Either way, travel from home to your first job and back from your last is normal business travel for a fitter with no fixed workplace, so keep a mileage log.
Bigger tool purchases, a new cordless drill set, an SDS drill, a laser level, are capital items but you can normally write the full cost off in the year of purchase through the Annual Investment Allowance. Smaller consumable tools and the bits, blades and fixings you get through are simply running costs. Keep receipts for everything; HMRC expects a fitter to spend on tools and PPE, but only if you can show it.
The private share of your van, phone and broadband must be excluded. Everyday clothing is never allowable, even sturdy trousers, but branded workwear and genuine PPE are. Parking fines and speeding tickets are never deductible. And the cost of getting set up before you actually start trading is pre-trading expenditure, claimed once you begin, not lost.
Take a fitter doing a mix of domestic supply-and-fit and some subcontract labour for a local shopfitter, with GBP 42,000 of income for the year, of which GBP 16,000 was CIS labour with GBP 3,200 already deducted at 20%.
Income: GBP 42,000 (domestic supply-and-fit GBP 26,000, CIS subcontract labour GBP 16,000)
Allowable expenses:
Taxable profit: GBP 42,000 minus GBP 16,700 = GBP 25,300
Income Tax: GBP 25,300 minus GBP 12,570 = GBP 12,730 at 20% = GBP 2,546
Class 4 NIC: GBP 12,730 at 6% = GBP 764
Tax and NIC due: GBP 3,310. But GBP 3,200 of CIS was already deducted at source, so the fitter actually owes only about GBP 110 once the CIS is offset, instead of writing a large cheque in January. Run your own figures through the sole trader tax calculator to sanity-check, and the CIS calculator if most of your work is subcontract labour.
For a blind fitter the tax refund usually hides in the CIS statements. Keep every monthly deduction statement and every tool and van receipt, and the January return turns into a rebate rather than a bill.
You must register for VAT once your taxable turnover passes GBP 90,000 in any rolling 12-month period. A fitter doing labour-only domestic work rarely gets near it, but supply-and-fit changes the maths, because the price of the blinds and shutters themselves counts towards turnover. A busy fitter installing made-to-measure stock across many jobs can cross GBP 90,000 faster than expected, so watch the rolling 12-month total, not just the tax-year figure. If most of your work is commercial fit-outs for VAT-registered businesses, voluntary registration can pay, because they reclaim the VAT you charge and you reclaim VAT on tools, the van and stock. Domestic-only fitters should weigh it carefully, as adding 20% to a homeowner's price either dents your margin or your competitiveness. Note that CIS contractors may also operate the VAT domestic reverse charge on construction services, which changes how you invoice them.
Making Tax Digital for Income Tax Self Assessment replaces the annual return with quarterly digital updates and a year-end finalisation. The thresholds are based on gross income, not profit:
For a fitter the gross test matters. Supply-and-fit turnover and CIS labour count gross, before deductions, so a fitter clearing modest profit can still be over a threshold on turnover. Instead of bagging up a shoebox of receipts each January, you record income and costs digitally as they happen and send HMRC a summary each quarter through compatible software. The upside is that capturing CIS statements, tool receipts and van mileage continuously makes the refund easier to claim and the year-end far less painful. Our MTD for sole traders guide walks through the quarterly rhythm in practice.
Not registering for CIS and being deducted at 30%. Registering drops the deduction to 20%, a real cash-flow gain across the year.
Losing CIS statements. Without them you cannot prove the tax already paid, and you risk leaving a refund unclaimed.
Recording CIS income net of the deduction. Report the gross labour and show the CIS deduction separately, otherwise your figures will not reconcile.
Mixing van methods. Once you choose mileage or actual costs for a vehicle, you must keep to it; switching mid-stream is not allowed.
Forgetting it is gross turnover for MTD and VAT. Supply-and-fit and CIS labour are tested gross, so a fitter on slim margins can still trip a threshold.
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