Commercial Electrical Installation Costs UK — Office, Retail and Industrial Electrical Work Pricing Guide (2026)

Commercial electrical work operates in an entirely different league from domestic installs. The regulations are more demanding, the projects more complex, and the pricing — when done correctly — considerably more rewarding. Whether you are quoting a small retail unit rewire or tendering for a full office fit-out, knowing what the market pays and how to price it accurately is the difference between a profitable contract and an expensive lesson.

This guide covers current 2026 pricing across all the main categories of commercial electrical work in the UK, plus the compliance requirements, quoting methodology, and marketing intelligence that help you win the jobs worth having.

Commercial vs domestic electrical: regulations and certification

The single most important distinction for electricians crossing from domestic to commercial work is the regulatory framework. Domestic work in England and Wales is governed by Part P of the Building Regulations, which requires notification to Building Control for notifiable work unless you are registered with a competent person scheme such as NICEIC, NAPIT, or ELECSA. This notification model does not exist in commercial buildings.

Commercial installations must comply with BS 7671:2018 (the 18th Edition Wiring Regulations, including Amendment 2:2022). This is not a statutory instrument in itself, but it is the recognised standard that satisfies the Electricity at Work Regulations 1989 and the Health and Safety at Work Act 1974. For any commercial premises, you must issue an Electrical Installation Certificate (EIC) on completion of new work, or an Electrical Installation Condition Report (EICR) for inspection work.

Scheme membership matters more in commercial work, not less. While Part P does not apply, clients — particularly facilities managers, property developers, and tenants fitting out leased space — routinely require contractors to hold NICEIC Approved Contractor, ECA membership, or NAPIT certification. These schemes provide third-party quality assurance, public liability cover verification, and a route for clients to raise complaints. Without scheme membership, you will be excluded from most formal tender processes.

• NICEIC Approved Contractor: the most widely recognised scheme for commercial electrical work. Annual fee circa £600–£1,200 depending on turnover. Requires assessed inspection of recent work.
• ECA (Electrical Contractors Association): trade body with its own competency scheme. Particularly valued by main contractors and developers in the commercial sector.
• NAPIT: broadly accepted for commercial work, strong in the domestic sector and increasingly common for smaller commercial projects.

For industrial work involving high-voltage systems (above 1,000V AC), additional competency requirements apply under the Electricity at Work Regulations and HSE guidance. Always confirm your scope of competency before pricing work involving HV switchgear or transformer substations.

Commercial electrician day rates (2026)

Day rates for commercial electricians vary considerably based on location, specialism, and whether you are pricing as a sole trader or providing a supervised team. The figures below reflect all-in contractor rates — what a client pays for labour, not what an employed sparky earns.

London and the South East attract a 20–30% premium on these figures. Night shift, out-of-hours, or confined space working will add further uplift — typically 1.5x to 2x standard day rate.

New commercial fit-out: office electrical costs

Office fit-out electrical work covers general power, lighting, data infrastructure, emergency lighting, and fire alarm connections. Costs are typically quoted per square metre of gross internal area and vary based on specification, number of floors, and the density of workstations.

For a 500m² Cat B office, expect to price electrical at £25,000–£40,000. A 2,000m² head office with high-spec finish could easily reach £160,000–£240,000 for electrical alone. These figures exclude main distribution upgrades or significant incoming supply works, which are priced separately.

Industrial 3-phase installation costs

Industrial electrical installations are defined by the loads they need to serve: heavy machinery, compressors, CNC equipment, dust extraction, and process heating all demand robust 3-phase supplies with appropriate protection devices. Costs scale sharply with connected load and the complexity of the distribution network.

• Small workshop or light industrial unit (up to 100A 3-phase): £3,000–£6,000 for board, sub-mains, and general power outlets.
• Medium industrial (100–400A 3-phase), new distribution board, sub-mains, machinery feeds): £6,000–£15,000.
• Large factory or heavy industrial (400A+, multiple sub-boards, motor starters, control panels): £15,000–£60,000+ depending on scope.

DNO (Distribution Network Operator) connection or supply upgrade costs are separate and can add £3,000–£20,000+ depending on whether a new service head, metering, or substation is required. Always clarify the scope of DNO works with the client before pricing — it is a common source of budget surprises on industrial projects.

Motor control circuits, variable speed drives, and PLC integration are specialist areas that command the higher end of specialist day rates. If this is outside your scope, sub-contracting this element and marking it up 15–25% is a sensible approach on larger tenders.

Retail unit rewire costs

Retail unit electrical work is driven by retail fitout standards, landlord requirements, and the density of display lighting, till points, and HVAC equipment. Rewiring or fitting out a retail unit typically involves replacing or upgrading the distribution board, installing track lighting circuits, power for display cabinets, till circuits, and fire alarm/emergency lighting connections.

High-end retail fit-outs with bespoke lighting schemes, automated dimming, and detailed feature lighting installations sit at the top of these ranges or beyond. Restaurants and food outlets add extraction, refrigeration circuits, and commercial kitchen connections which can add £3,000–£8,000 to the electrical scope.

Distribution board and consumer unit upgrades

Upgrading an existing commercial distribution board or installing a new one is a common standalone job, particularly during building refurbishments, changes of use, or after an EICR has identified the existing board as non-compliant.

• Small commercial consumer unit (up to 12 ways, single-phase): £800–£1,400 supplied and fitted.
• Medium commercial board (24–36 ways, single-phase or 3-phase): £1,400–£2,500.
• Large 3-phase distribution board with MCCB protection: £2,500–£6,000+.
• Full sub-main distribution with multiple sub-boards: priced individually per board, plus sub-main cable runs at £15–£40/metre depending on cable size.

Always allow for making good after chasing and surface trunking where concealment is not possible. In occupied commercial premises, out-of-hours working to avoid business disruption adds 1.5x to labour costs and should be costed explicitly in the quote.

Emergency lighting installation costs

Emergency lighting is a statutory requirement under the Regulatory Reform (Fire Safety) Order 2005 for all non-domestic premises. It must comply with BS 5266-1 and be maintained and tested regularly. Commercial electricians are well placed to install and service emergency lighting systems as part of broader fit-out or compliance work.

• Individual emergency lighting fitting (self-contained, maintained or non-maintained): £25–£60 per fitting supplied and installed, depending on type and accessibility.
• Central battery system fitting (wired back to central inverter): £40–£80 per fitting, plus £800–£2,500 for the central battery unit.
• Full system for small premises (10–20 fittings): £1,500–£3,000.
• Full system for large commercial premises (50+ fittings): £4,000–£8,000+.

Annual testing and maintenance contracts for emergency lighting typically run at £150–£500/year for small premises, rising to £1,000–£3,000/year for larger buildings. Offering a maintenance contract alongside installation improves your recurring revenue and gives clients compliance confidence.

Fire alarm system costs

Fire alarm design and installation for commercial premises must comply with BS 5839-1:2017. The grade and category of system required depends on the risk assessment and the type of building. As an electrical contractor, you may install the system yourself (if competent and appropriately insured) or act as principal contractor and subcontract the fire alarm element.

FIA (Fire Industry Association) membership and BAFE SP203-1 certification are increasingly required for fire alarm installation on commercial and public sector projects. If you are serious about commercial fire alarm work, these accreditations are worth pursuing.

Data cabling: Cat6 and Cat6a structured cabling costs

Structured data cabling is a natural add-on to commercial electrical fit-outs. Most commercial electricians quote this alongside power work or bring in a specialist cabling sub-contractor. Pricing is typically quoted per data drop (one cable run from patch panel to outlet).

• Cat6 data drop (installed, tested, certified): £150–£250 per drop for standard office environments.
• Cat6a data drop (installed, tested, certified): £200–£350 per drop — required for 10Gbps applications and runs over 55m.
• 24-port patch panel, rack, and labelling: £400–£800 per rack position.
• Data cabinet / comms room fit-out: £1,500–£5,000+ depending on size and specification.

Testing and certification to ISO 11801 / TIA-568 standards using a Fluke or IDEAL certified tester is non-negotiable on commercial jobs. Build the test time and certification document into your quote — it takes roughly 5–10 minutes per drop to test and certify properly.

Commercial EV charging installation costs

The commercial EV charging market is growing rapidly. Workplace, retail, and hospitality venues are all being pushed toward providing EV charging, driven by planning conditions, corporate sustainability targets, and government grants via the Workplace Charging Scheme (WCS). This is high-value work with strong margins if you have the right competencies.

For multi-bay installations, civil works (groundworks, ducting, cable pulling) add significant cost — budget £500–£2,000 per bay for cabling and civils in a car park installation. Load management and smart charging software integration is increasingly required by larger clients and adds £200–£800 per charger in hardware and commissioning.

OZEV-authorised installer status is required to offer clients access to government grant schemes. Registration is free but requires documented evidence of competency and £5 million public liability cover.

EICR for commercial premises

Electrical Installation Condition Reports for commercial properties are required by landlords, insurance companies, and the Health and Safety Executive. Unlike domestic EICRs which are priced by number of circuits, commercial EICRs are typically priced by size, complexity, and testing time.

• Small office or retail unit up to 100m²: £150–£300.
• Medium commercial premises 100–500m²: £300–£500.
• Large commercial or industrial premises: £500–£2,000+ depending on the number of circuits, distribution boards, and access constraints.

Commercial EICRs are due every 5 years for most premises, or on change of occupancy. The Health and Safety (Safety Signs and Signals) Regulations and the Electricity at Work Regulations effectively mandate regular testing — the EICR is the accepted method of demonstrating compliance.

PAT testing costs

Portable Appliance Testing is not a statutory requirement but is considered best practice under the Health and Safety at Work Act. Most commercial landlords and facilities managers expect annual or biennial PAT testing as part of their health and safety management.

• Per item tested (on-site, including pass/fail label and report): £1–£3 per item.
• Minimum call-out charge: typically £50–£100, making very small jobs uneconomical without bundling.
• Annual contract for 50–200 items: £100–£400/year.

PAT testing alone is low-margin work. The value is in using it as a door-opener for EICRs, distribution board upgrades, and ongoing maintenance relationships. Always cross-sell when on site.

BS 7671 compliance: what electricians must document

BS 7671:2018 (18th Edition, Amendment 2:2022) requires specific documentation for every commercial installation. Getting this right protects you legally and gives clients confidence in your professionalism.

• Electrical Installation Certificate (EIC): required for all new installations and significant alterations. Must be signed by the designer, installer, and inspector — which may all be the same person on smaller jobs, but should be separated on complex projects.
• Schedule of Inspections: a checklist confirming that all required inspection checks have been carried out in accordance with Part 6 of BS 7671.
• Schedule of Test Results: recorded test results for every circuit — insulation resistance, continuity, loop impedance, RCD operating times, and polarity. These must be completed before the installation is energised.
• Minor Works Certificate: for additions to existing circuits that do not constitute new circuits.
• Operation and Maintenance (O&M) manuals: expected on commercial projects over a certain value. Include as-fitted drawings, test certificates, equipment data sheets, and maintenance schedules.

Digital certification through NICEIC Portal, Smark, or similar platforms is now standard. Paper certificates are increasingly unacceptable to commercial clients and facilities managers who manage multiple sites.

Quoting commercial electrical work: takeoff, materials, and contingency

Commercial electrical pricing requires a more disciplined approach than domestic work. Guessing materials from experience is not good enough on a £50,000 contract — a 10% materials error costs £5,000.

The takeoff

A proper material takeoff involves counting every point on the drawings: lighting positions, socket outlets, data outlets, switches, isolators, equipment feeds, and control devices. From that, you build out the associated materials — cable lengths (with a 10–15% wastage factor), containment, accessories, and equipment. Software such as Causeway, Procore, or even a well-structured Excel template will speed this up significantly on larger jobs.

Materials pricing and uplift

Price materials from your current supplier quotes, not from memory. Trade prices change frequently. Apply a materials margin of 15–25% to cover buying errors, returns, and the cost of your procurement time. On complex jobs with specialist equipment, apply a higher margin (20–30%) on items you are less familiar with.

Contingency allowance

Always include a contingency in your commercial quotes. For straightforward fit-outs in new-build or recently refurbished buildings, 5–8% is appropriate. For older buildings, refurbishments with concealed services, or projects where drawings are preliminary, 10–15% is prudent. Make the contingency explicit in your quote — it demonstrates commercial awareness rather than hiding a slush fund.

Winning commercial contracts: tender process and pricing strategy

Commercial electrical work is usually won through formal or informal tender processes. Understanding how these work gives you a significant advantage over competitors who simply submit a price without reading the room.

The tender process

Most commercial projects above £20,000 will involve a tender pack: drawings, specifications, schedules of work, and commercial terms. You are typically given 2–4 weeks to submit a priced bill of quantities or a lump sum with a detailed breakdown. Read the specification before pricing — clients specify the standard of materials, cable types, containment systems, and certification they expect. Pricing to a cheaper specification and then being asked to upgrade on site destroys your margin.

Pricing strategy

Do not buy work by pricing at cost. Commercial clients expect professional contractors who price to a sustainable margin — typically 12–20% net on commercial electrical work. If you consistently win every tender, you are priced too low. A 30–40% win rate on commercial tenders is a healthy benchmark.

Use a cover price when you are too busy or the job is not a good fit. Submitting a deliberately high price keeps you in the tender database without obligating you to a job you cannot resource properly.

Build relationships with main contractors, M&E consultants, and property developers who place repeat work. One strong relationship with a regional developer can deliver five to ten projects a year without open tendering.

How Trade2Base helps commercial electricians win the right tenders

Winning commercial electrical contracts requires more than good pricing — it requires knowing which marketing activity is actually generating your tender opportunities. Many commercial electricians invest in LinkedIn, paid search, referral networks, and trade directories without any clear picture of which channel is delivering the enquiries that convert to profitable contracts.

Trade2Base tracks every lead from first contact through to invoice, tagging the marketing source so you can see not just where your enquiries come from, but which channels are generating the commercial tenders — as opposed to the domestic call-outs you are trying to move away from.

If your LinkedIn activity is generating five commercial enquiries a month and your Checkatrade listing is generating thirty domestic calls, that data changes how you allocate your marketing budget. Trade2Base surfaces exactly that, so you can double down on what is working and stop paying for what is not.