What work is covered by CIS?

As of October 2026, the Construction Industry Scheme (CIS) covers most construction work in the UK: site preparation, building, alterations, repairs, decorating, demolition and installing systems such as heating, lighting and water. Carpet fitting, architecture and deliveries are excluded.

The legal list is section 74 of the Finance Act 2004, and HMRC explains how it reads it in the CIS 340 guide and its CIS manual. This page follows those sources as checked on 16 October 2026.

What the law includes

Section 74 lists the work that counts as construction operations:

• building, altering, repairing, extending, demolishing or dismantling buildings and structures, permanent or temporary
• the same work on things that form part of the land, such as walls, roads, power lines, pipelines, sewers and drainage
• installing systems of heating, lighting, air conditioning, ventilation, power supply, drainage, sanitation, water supply or fire protection in a building
• internal cleaning while a building is being built, altered, repaired or restored
• painting or decorating inside or outside a building
• work that is part of, prepares for or finishes any of the above, including site clearance, excavation, foundations, scaffolding, site restoration and landscaping

What the law leaves out

The same section excludes oil and gas drilling, mineral extraction, making building components or materials and delivering them to site, the professional work of architects, surveyors and design consultants, wholly artistic works such as sculptures and murals, signwriting and advertising boards, seating, blinds and shutters, and security systems such as burglar alarms, CCTV and public address systems.

Trade by trade

The trade rows come from CIS 340 Appendix C and HMRC's manual pages on building service systems, cleaning, fencing and floor coverings. HMRC says its list is not exhaustive, and the A to Z index at CISR14330 covers more types of work.

Three rules that decide borderline jobs

Installation versus repair. For heating, lighting, power, water and drainage, CIS covers installing a whole system, not repairing or extending one. HMRC's manual gives fixing a leaking radiator, replacing a tap and wiring extra sockets as examples outside CIS. A complete rewire counts as an installation. The repairs and maintenance guide works through more examples.

Mixed contracts. If one contract includes any construction work at all, every payment under it is covered. HMRC's example is a single contract to repair a gutter and replace roof tiles: all of it falls in.

The wider project. Some work is covered only because it finishes or prepares for a building job. Tree felling to clear a housing site is covered; tree felling in ordinary forestry is not. The same work can be in on one job and out on the next.

What this means for you

Whether CIS applies depends on each contract, not on your trade name. An electrician can be inside CIS on a new-build rewire in the morning and outside it on a fault call in the afternoon. If a contractor takes CIS from a job that is wholly outside the scheme, CIS 340 says that should not happen, so raise it with them.

Payments for work outside CIS still count as business income on your tax return, and they count towards the Making Tax Digital threshold too.

Steps to check if a job is covered

1. Ask who is paying you. A private homeowner paying direct is not a CIS contractor.
2. Check the work against the table above and the section 74 list.
3. For systems work, ask whether you are installing a whole system or repairing part of one.
4. Look at the whole contract. If any part is construction work, all of it is covered.
5. If you are still unsure, the contractor or subcontractor guide and HMRC's CIS helpline can help.

The free MTD check shows when Making Tax Digital starts for you, and the trades section has more on CIS.