Pricing a house rewire as a self-employed CIS electrician

What a rewire actually costs a CIS subcontractor to deliver

Trade cost guides published in 2026 put a full rewire of a three-bedroom house at roughly £5,000 to £7,500, spread over five to seven working days. Checkatrade's guidance puts the national average for a full house rewire at around £6,500, and other cost guides quote a wider £3,500 to £12,000 across all property sizes. Those are retail ranges quoted to homeowners, and they are the numbers your customer has already read before they ring you.

They are not, however, your cost of delivery, and they are certainly not what a main contractor will pay you for the same work on a refurbishment. Pricing a rewire profitably means building the number from the bottom up, from operative days, materials, certification and travel, then checking it against the market range rather than starting from the market range and hoping. This guide covers the cost stack, the compliance costs that belong in the quote, the margin traps specific to rewires, payment staging, and the tax consequences that only show up after the job is priced.

Trade-reported rewire prices by property size, and where a subcontractor sits

The table below consolidates ranges published by UK trade cost guides during 2026. Treat them as market context for what a domestic customer expects to pay, not as a rate card. All figures are quoted before VAT unless the guide states otherwise, and they generally exclude making good.

Property	Trade-reported price range	Typical duration reported
1 or 2 bed flat	£3,000 to £4,000	2 to 4 days
2 bed house	£4,000 to £5,500	3 to 4 days
3 bed house	£5,000 to £7,500	5 to 7 days
4 bed house	£6,500 to £9,000	7 to 10 days
5 bed house	£7,000 to £12,000	10 to 14 days

Three adjustments are consistently reported across those guides. London and the South East carry a premium of roughly 20% to 30%. An empty property runs 15% to 25% cheaper than the same job occupied, because there is no furniture to move, no dust protection to manage and no working around a family. Making good adds a further 15% to 25% if you are including it.

On the labour side, 2026 trade guides put the self-employed domestic electrician day rate at around £220 to £300 for a standard eight-hour day, rising to roughly £280 to £380 in London and the South East. Those are the numbers to test your own build-up against.

Building the price: the cost stack for a rewire subcontractor

A rewire price has six components, and underpricing almost always comes from omitting one of the last three rather than getting the first three wrong.

• Operative days. First fix (lifting floors, chasing, cable runs, back boxes), second fix (accessories, consumer unit, terminations), then inspection and testing. Count operative days, not calendar days. A three-bed done in six calendar days with a mate on site for four of them is ten operative days.
• Materials. Cable, back boxes, accessories, the consumer unit and protective devices, fixings, fire-stopping and consumables. On a supply-and-fix rewire this is commonly a third or more of the invoice value.
• Certification and notification. Testing time, the Electrical Installation Certificate with full schedules, and either your competent person scheme notification or a building control fee.
• Travel and vehicle. Every day on site is a return journey. Claimed at the Approved Mileage Allowance Payments rate of 55p per mile for the first 10,000 business miles from 6 April 2026 (25p thereafter), a 30-mile round trip across a six-day job is £99 of cost that most quotes silently absorb.
• Overhead recovery. Scheme registration, public liability and tools insurance, calibration of test equipment, phone, accountancy, and the unbilled hours spent surveying and quoting. Spread across your realistic billable days in the year, this is rarely less than £40 to £60 a day.
• Risk and margin. The contingency for what the floorboards are hiding, plus actual profit.

Test equipment deserves a note of its own. Multifunction testers, insulation resistance testers and their annual calibration are a substantial ongoing cost for an electrician and are dealt with through capital allowances rather than as a straight expense. Our guide to vans, tools and capital allowances for trades in 2026/27 covers how to claim them, and the wider expenses CIS subcontractors can claim sets out the mileage, PPE and insurance side.

Part P notification and certification costs the subcontractor carries

A full rewire installs new circuits and replaces the consumer unit, and both are notifiable electrical work in dwellings in England and Wales under Part P of the Building Regulations. Any work in a special location, which includes every room containing a bath or shower, is notifiable in its own right.

There are three routes. You self-certify as a member of a government-approved competent person scheme (NICEIC, NAPIT, ELECSA and BRE Certification are the principal electrical schemes) and notify through the scheme, which issues the Building Regulations Compliance Certificate. You notify local authority building control before starting, where trade sources report typical fees of £250 to £400 for electrical work. Or, if unregistered, you have the work certified by a registered third party. The competent person route carries no per-job fee beyond your annual scheme registration, which is why the annual fee is worth checking directly with your scheme and then recovering across your billable days rather than treating it as a sunk cost.

A full rewire is certified with an Electrical Installation Certificate and full schedules of inspection and test results. A Minor Works Certificate does not cover it. Testing and certification time is chargeable time and should appear in your build-up.

One live point for 2026 quotes: BS 7671:2018+A4:2026 was published in April 2026, and the previous Amendment 3 version remains a valid standard only until 15 October 2026. Installations completed after that date are designed and certified to Amendment 4, which among other changes retains the requirement for arc fault detection devices on single-phase socket-outlet final circuits up to 32A in houses in multiple occupation, purpose-built student accommodation, care homes and high-rise residential buildings, while continuing to recommend them elsewhere. If you are quoting an HMO rewire, the AFDD requirement is a specification and cost question, not an optional extra.

Five margin traps that turn a profitable rewire into a bad CIS job

Rewires go wrong in predictable ways. Each of these is a variation clause waiting to be written.

Old wiring that will not draw out. Perished rubber, lead-sheathed or early PVC cable frequently cannot be used as a draw route for the new run, which turns a straightforward replacement into fresh chasing and floor lifting. Survey before you quote.

Earthing and bonding that is not there. Older properties routinely need main protective bonding to gas and water, and sometimes a new main earthing arrangement or supplier involvement. That is days, not hours, and it is not part of a rewire quote unless you say it is.

Plaster that fails. Lime plaster and old lath come away in sheets when chased. The scope boundary between "chased and made safe" and "made good ready to decorate" needs to be written down. Trade guides put making good at 15% to 25% on top of the rewire cost, so this is not a rounding error.

Scope creep by conversation. Additional sockets, an outside light, a garage supply, a shower circuit. Each is a fair variation and each is unpaid if it is agreed verbally at the top of a ladder. Price additions in writing before you fit them.

Paying a mate without operating CIS. This one is a compliance trap rather than a pricing one. The moment you pay another self-employed worker for construction work, you are a contractor under the Construction Industry Scheme. You must verify them, deduct at 20% or 30%, issue payment and deduction statements and file a monthly CIS300 by the 19th. From 6 April 2026 a nil return is mandatory for every tax month with no payments unless you pre-notify inactivity, with penalties starting at £100 for one day late. See our guide to the CIS nil return for how that obligation now works.

Payment staging and cash flow for a rewire subcontractor

A rewire is materials-heavy at the front end and cash-negative for the first week if you fund the wholesaler bill yourself. Stage the payments so the job pays for itself as it progresses.

Stage	Typical proportion	Trigger
Deposit or materials payment	25% to 35%	On acceptance, before materials are ordered
First fix complete	30% to 40%	Cables run, back boxes fitted, before plastering
Second fix complete	20% to 30%	Accessories and consumer unit fitted and energised
Final payment	10% to 15%	On issue of the Electrical Installation Certificate

Holding the certificate until final payment is legitimate and effective, because the customer needs it for their records, their insurer and any future sale. On subcontract work for a main contractor the position is different: expect application-for-payment cycles, and expect a retention of typically 3% to 5% to be held. Retentions carry their own CIS treatment, covered in our guide to CIS and retention payments. Payment run length matters too, and our analysis of how long large construction firms take to pay subcontractors is worth reading before you agree terms with a new contractor.

Worked example: a 3-bed supply-and-fix rewire as a CIS subcontractor

An electrician takes a full rewire of an occupied three-bed semi as a subcontractor to a small developer. Six calendar days on site, with a second operative for four of them.

Line	Amount
Labour: 10 operative days charged	£2,900
Materials: cable, accessories, consumer unit, fixings	£1,450
Invoice total	£4,350
CIS deducted at 20% on labour only (£2,900 x 20%)	£580
Net payment received	£3,770
Deduction if the invoice had shown one total (£4,350 x 20%)	£870
Cash-flow cost of failing to split the invoice	£290

Against that £4,350, the electrician's own costs on the job might run to £1,450 of materials, roughly £900 paid to the second operative (itself a CIS payment requiring verification and a monthly return), £99 of mileage at 55p, and around £360 of overhead recovery at £60 a day across six days. That leaves approximately £1,541 of profit before tax, or about 35% of the invoice value. Lose two days to perished cable and unrecorded bonding work, and that margin halves.

The £290 in the table is not lost permanently, because over-deducted CIS is recovered through your Self Assessment refund claim or, for a company, through the EPS route. It is a cash-flow loss for up to a year on a single job, which is why the labour and materials split on a rewire invoice matters so much. The mechanics are set out in full in our guide to splitting labour and materials on a CIS invoice.

Before you commit to a price, run the numbers through our CIS invoice splitter to see the deduction on your labour and materials split, and the CIS deduction calculator to check what should actually land in your account.

Whether CIS applies at all, and the VAT position on a rewire

A rewire for a private householder is not within the Construction Industry Scheme, because a homeowner having work done on their own home is not a contractor. You invoice in full, no deduction is made, and the income goes on your Self Assessment return in the ordinary way. The same rewire carried out for a developer, a housebuilder, a landlord operating as a business, or a main contractor is CIS work and a deduction applies. Our guide to what construction work is not covered by CIS sets out the boundary in detail.

VAT follows a different logic again, and on rewires there are three positions to keep straight:

• Direct to a householder, standard property: 20% VAT if you are VAT-registered.
• Direct to the owner of a dwelling empty for two years or more: the reduced 5% rate under section 8 of VAT Notice 708. Section 2.1.3 of the same notice makes subcontractor supplies on that job standard-rated, so this relief only reaches the business contracting with the owner.
• As a subcontractor to a VAT-registered and CIS-registered contractor who is not the end user: the domestic reverse charge applies, you invoice with no VAT, and the customer accounts for it. New-build housing is zero-rated and outside the reverse charge.

Getting this wrong on a large rewire is expensive in both directions. Our guide to the VAT reverse charge for CIS subcontractors covers the end-user rules and the de minimis position.

The thresholds a big rewire year pushes you across, and what MTD means

Rewires are large-ticket jobs, and a run of them changes your tax position faster than a year of small works. Three thresholds are worth watching as you quote.

Threshold	Figure	Consequence
VAT registration	£90,000 taxable turnover in any rolling 12 months	Compulsory registration; reverse charge then applies on qualifying subcontract work
MTD for Income Tax, from 6 April 2027	Qualifying income over £30,000 in 2025/26	Digital records and quarterly updates
MTD for Income Tax, from 6 April 2028	Qualifying income over £20,000 in 2026/27	Digital records and quarterly updates

Qualifying income for Making Tax Digital is gross turnover before expenses and before CIS deductions. An electrician invoicing £34,000 of supply-and-fix rewires and receiving considerably less after materials costs and 20% deductions is still measured on the £34,000. The £50,000 threshold has applied since 6 April 2026. Our guide to MTD for Income Tax and CIS explains how quarterly updates work alongside CIS payment statements.

Volume of this kind is also the point at which the structure question becomes real. Sustained rewire turnover, a second operative on the books and a growing materials spend all change the sole trader against limited company calculation, and gross payment status becomes worth pursuing once the £30,000 net CIS turnover test is comfortably met. Our comparison of CIS as a sole trader or limited company is the place to start.

A rewire priced from the bottom up (operative days, materials, certification, travel, overhead, risk) will sit inside the market range far more often than one priced by copying a competitor's number. The compliance costs are real costs and belong in the quote, and the labour and materials split belongs on the invoice, because that is what determines how much of your own money HMRC holds until you file. Get both right and a rewire is one of the most profitable jobs on a domestic electrician's books.

If you want your rewire pricing, your CIS position and your expense claims looked at together rather than in isolation, our accounting service for electricians covers the whole picture.