What is TrustMark? It is the UK’s government-endorsed quality scheme for work done in and around the home, and it is one of a handful of badges on a Kent builder’s van that actually means something. TrustMark has run since 2005, licenses and audits more than 40 scheme providers, and covers over 18,000 registered businesses across 115 types of work. But it is not the only badge worth checking, and some of the others are a legal requirement rather than a nice extra. This page explains what each common trade accreditation proves, which ones you need for which job, and how to check a claim in a couple of minutes before you sign.
What TrustMark is and what it is not
TrustMark is a not-for-profit company (TrustMark 2005 Ltd) that operates under a licence from the Department for Business and Trade. It does not vet tradespeople directly. Instead it licenses scheme providers, bodies such as NICEIC and NAPIT, and those providers check and monitor the businesses that sign up through them.
A TrustMark registered business has to meet three sets of rules:
- The Framework Operating Requirements, which cover business suitability, technical competence, consumer protection, monitoring, customer service and complaint handling.
- The Code of Conduct, which covers published business information, written quotes and contracts, surveys, design, installation, handover, invoicing and complaints.
- The Customer Charter, which commits the business to follow through on agreed work, act professionally, be transparent, give clear contracts and try to resolve concerns.
Breaking the Code of Conduct or Customer Charter can lead to a business’s registration being suspended or withdrawn.
What TrustMark does not do is investigate individual complaints itself. If something goes wrong, the scheme provider the business registered through is responsible for helping resolve the dispute, and may point you to an independent alternative dispute resolution (ADR) service for complicated cases. TrustMark’s role is to check that the provider followed the process. So when you check a business, note which scheme provider it is registered through as well as the TrustMark badge itself.
The badges that are a legal requirement
Some accreditations are not optional. For these jobs, hiring someone without the right registration can break the law or leave you without the paperwork you need to sell the house.
Gas Safe Register: any gas work
Anyone fitting, moving or servicing a gas boiler, hob, fire or pipework must be on the Gas Safe Register. There is no exception for small jobs. Every registered engineer carries an ID card with a licence number and a list of the appliance types they are qualified for; check that the card covers your job, not just gas in general.
Competent person schemes: windows, electrics, heating
Most building work needs building regulations sign-off. A competent person scheme lets a registered installer self-certify certain work, so you do not need a separate application to building control. The government’s list of competent person schemes sets out who covers what. The ones you will meet most often in Kent homes:
- Replacement windows, doors and rooflights: FENSA, CERTASS, Certsure, NAPIT, Blue Flame Certification and ASSURE.
- Electrical work in a home: Certsure (which runs NICEIC), NAPIT, BESCA, Blue Flame Certification and OFTEC.
- Heating and hot water: Gas Safe Register, HETAS (wood and solid fuel), OFTEC (oil), Certsure, NAPIT, APHC, BESCA and Blue Flame Certification.
If an installer is not on a scheme for that work, either they or you must notify building control, which costs money and time. Ask at quote stage who will notify. Keep the certificate you receive at the end: a buyer’s solicitor will ask for it when you sell.
The badges that unlock grants
Some government money is only paid if the installer holds the right certification.
- MCS for heat pumps: the Boiler Upgrade Scheme pays £7,500 towards an air source or ground source heat pump in England and Wales, and the installer applies on your behalf. GOV.UK tells homeowners to get quotes from MCS certified installers. Our Boiler Upgrade Scheme guide covers the full rules.
- TrustMark for insulation schemes: energy company insulation schemes such as ECO4 and the Great British Insulation Scheme have required installers to be TrustMark registered and certified to PAS 2030. If you are offered “free” insulation, ask for both the TrustMark registration and the PAS 2030 certificate before anyone drills a wall.
An installer without MCS cannot get you the Boiler Upgrade Scheme grant, however good their price. If a heat pump is on your list, our page on choosing heat pump installers in Kent goes through the checks in more detail.
Kent Trading Standards Checked
Kent County Council runs its own vetted list, Trading Standards Checked. Traders send documents for Kent Trading Standards to review, and the scheme exists to keep rogue traders out and give residents a list they can rely on. Searching it is free for residents and it is funded by trader membership fees. Search it at kent.gov.uk/tschecked or call 03000 41 64 38.
It is a useful local check, especially for smaller jobs such as roofing repairs, driveways and gutter clearing, where doorstep selling is most common. It does not replace Gas Safe or a competent person scheme for regulated work.
Trade bodies and review sites: useful, but different
A lot of logos on a website are trade association memberships or review-site listings. Some of these do real vetting; others are paid directories. Before giving one any weight, ask three questions:
- Does anyone inspect the work, or only check paperwork and insurance?
- Is there a complaints process with an independent final step, such as an ADR service or ombudsman?
- Can you check the membership on the body’s own website, not just on the trader’s?
A logo that fails all three is marketing. A body that passes all three is worth knowing about even if it is not government endorsed.
How to check any claim in five minutes
- Get the exact business name and registration number from the quote, not from the van.
- Search the register yourself on the scheme’s own website: TrustMark’s “find a tradesperson” search, the Gas Safe Register, the competent person scheme’s register, MCS, or Kent Trading Standards Checked.
- Match the trading name and address. Rogue traders sometimes borrow a real firm’s number. If the name on the register is a different company, ask why.
- Check the scope. A Gas Safe engineer qualified for boilers is not automatically qualified for gas fires; an electrician registered for domestic installation work is not automatically a heat pump installer.
- Check insurance separately. Ask for the public liability certificate and the expiry date. Our guide to what insurance your builder should have lists what to ask for.
Do this before you accept a quote or pay a deposit. If you are weighing several prices, our guide to comparing builders’ quotes shows how to line them up properly.
Which accreditation for which job
- New boiler or gas appliance: Gas Safe (legal requirement).
- Rewire, new circuits, consumer unit: an electrical competent person scheme such as NICEIC or NAPIT, or building control notification.
- Replacement windows and doors: FENSA, CERTASS or another window competent person scheme.
- Wood burner or stove: HETAS.
- Heat pump with a grant: MCS.
- Insulation under an energy company scheme: TrustMark plus PAS 2030.
- Extensions, kitchens, bathrooms, roofing: no single legal badge, so TrustMark, Kent Trading Standards Checked, references and a written contract carry most of the weight.
Frequently asked questions
What is TrustMark?
TrustMark is the government-endorsed quality scheme for work in and around the home, set up in 2005. It licenses over 40 scheme providers, who vet and monitor more than 18,000 registered businesses against TrustMark’s Framework Operating Requirements, Code of Conduct and Customer Charter.
Is TrustMark a legal requirement for builders?
No. Most work can legally be done without it. It is required to deliver some government-funded schemes, such as energy company insulation schemes. Gas Safe registration, by contrast, is a legal requirement for gas work.
Does TrustMark handle complaints about a builder?
Not directly. The scheme provider the business registered through handles the dispute and may refer complex cases to an independent alternative dispute resolution service. TrustMark checks that the provider followed the right process.
What is the difference between FENSA and TrustMark?
FENSA is a competent person scheme: it lets window installers self-certify that replacement windows and doors meet building regulations. TrustMark is a broader quality scheme covering trading standards, customer service and complaints across many trades.
Do I need an MCS installer for a heat pump?
If you want the Boiler Upgrade Scheme grant, yes. GOV.UK tells homeowners to use MCS certified installers, and the installer applies for the £7,500 on your behalf.
How do I check if a trader is really registered?
Search the scheme’s own register using the exact business name, then check the name, address and scope of work match the quote. Never rely only on a logo on a van or website.
Planning work on a Kent home? Contemporary Structures has guides on extensions, roofing, windows and heating to help you plan the job and brief the right trades.
Related guides
- Conservatory Roof Replacement vs Glass Film: Which Fixes a Too-Hot, Too-Cold Conservatory?
- Air Source Heat Pump Cost in 2026 After the £7,500 Grant: What You Actually Pay
- Do You Need Planning Permission for a Rear Extension in Kent? 2026 Permitted Development Rules
- How Much Does a Conservatory Base Cost in the UK? (2026 Price Guide)
- Do You Need a Party Wall Agreement for a Rear Extension? Cost and Rules Explained
- Underfloor Heating vs Radiators for a Home Extension: Cost, Running Bills and Which to Choose
- How Much Does a House Extension Cost in 2026? Full UK Price Breakdown
- Loft Conversion Cost and Types: Dormer, Hip-to-Gable and Velux Explained
- House Extensions: The Complete UK Homeowner’s Guide
- Single Storey Extension Ideas, Costs and Planning Rules
- Double Storey Extensions: Costs, Designs and What You Can Build
- Side Return Extensions Explained: Cost, Light and Layout
- Garage Conversion Guide: Cost, Building Regs and Best Uses
- Extension vs Moving House: Which Is Better Value in Kent?
- Wraparound vs Rear Extension: Cost and Space Compared
- House Extension Builders in Kent: Costs, Lead Times and How to Choose
- Conservatory Guide: Styles, Costs and How to Choose One
- How Much Does a Conservatory Cost in 2026? UK Prices by Type
- Conservatory vs Orangery vs Extension: Which to Build?
- Conservatory Roof Options: Glass, Polycarbonate and Tiled Compared
- How to Keep a Conservatory Warm in Winter and Cool in Summer
- Tiled Conservatory Roof Cost and Replacement Process Explained
- Conservatories in Kent: Choosing an Installer, Costs and What to Ask
- Roofing Guide: Repairs, Replacement, Materials and Costs
- New Roof Cost UK 2026: Replacement Prices by Roof Type
- Roof Repair Cost UK 2026: Slipped Tiles and Flashing Prices
- 7 Signs Your Roof Needs Replacing (and What You Can Ignore)
- Flat Roof vs Pitched Roof: Cost, Lifespan and Best Uses
- EPDM vs Felt vs Fibreglass Flat Roofs Compared
- Roof Tile Types Explained: Clay, Concrete and Slate Compared
- Fascias, Soffits and Guttering: When to Replace and What It Costs
- How to Find a Good Roofer: Vetting Checklist for UK Homeowners
- Roofers in Kent: Costs, How to Choose and What to Ask in 2026
- Kitchen Renovation Guide: Planning, Cost and Design in 2026
- How Much Does a New Kitchen Cost in 2026? UK Price Guide
- Kitchen Layout Ideas: Galley, L-Shape, Island and Open Plan
- Worktops Compared: Quartz vs Granite vs Laminate vs Solid Wood
- Fitted vs Bespoke vs Flat-Pack Kitchens: Cost and Quality
- Kitchen Island Ideas, Sizes and Costs: A 2026 UK Guide
- Open Plan Kitchen Diner: Costs, Layouts and Knock-Through Rules
- How Long Does a Kitchen Fitting Take? Realistic UK Timeline
- Kitchen Fitters in Kent: Costs and How to Choose (2026)
- Bathroom Renovation Guide: Planning, Cost and Layout
- New Bathroom Cost 2026: What You’ll Pay in the UK
- Small Bathroom Ideas: Layouts That Feel Bigger
- Wet Room Cost 2026: £2,000 to £9,000 Fitted, by Size
- En Suite Cost and Minimum Size: £4,000 to £10,000 in 2026
- Electric vs Mixer vs Power Shower: What Your Boiler Allows
- Bathroom Underfloor Heating Cost: 16p an Hour to Run
- Window Replacement Cost 2026: £350 to £600 Per uPVC Window
- uPVC vs Aluminium Windows: the 1.4 U-Value Rule
- How Long Does a Bathroom Take to Fit? 5 to 10 Working Days
- Double vs Triple Glazing: Part L Still Stops at 1.4
- Bathroom Fitters in Kent: What to Ask Before You Pay
- Sash Window Repair or Replace? What Kent Councils Allow
- Bifold vs Sliding Doors: What Building Regs Actually Set
- Composite Door Cost 2026: £550 to £2,350 Fitted
- Window Energy Ratings: Band B Is the Rule, Not C
- Replacement Windows: the 1.4 U-Value and Vent Rules
- Double Glazing Kent: the 1.4 U-Value Every Quote Must Hit
- Heat Pumps in Kent: the £7,500 Grant and the 1.5m³ Rule
- Heat Pump vs Gas Boiler: Break-Even Is a SCOP of 3.0
- Permitted Development Rights: The 8m Rear Extension Rule
- Air Source vs Ground Source Heat Pump: £13k or £26k?
- Building Regulations Approval: Kent Fees, 10-Year Rule
- Boiler Upgrade Scheme: £9,000 Grants From 21 July 2026
- New Boiler Cost 2026: £1,800 to £4,500 Fitted
- Do Heat Pumps Work in Old Houses? Yes, With 3 Conditions
- Heat Pump Installers in Kent: 8 Checks Before You Sign
- House Rendering in Kent: When the Wall Must Be Insulated
