Step 1: What qualifications do you need?
There is no single "plumbing licence" in the UK. What you need is proof of competence that customers, insurers and trade schemes will accept.
The National Careers Service sets out the routes into plumbing as of October 2026:
College:
courses such as plumbing studies or plumbing and domestic heating, with a Level 2 diploma given as an example.
Apprenticeship:
Level 3 options such as Plumbing and Domestic Heating Technician.
On the job:
starting as a plumber's mate and training up.
It also notes you'll need a CSCS card or equivalent to work on a construction site.
Qualifications matter for more than competence. For example, APHC says members who hold a suitable plumbing NVQ Level 2 and a recognised water fittings regulations certificate can join WaterSafe free (as of October 2026). WaterSafe approval gives customers and water companies a way to check you.
Step 2: Do you need to be Gas Safe registered?
Only if you will do gas work, but if you will, it is a legal requirement.
HSE says "Anyone employed to work on gas appliances in domestic premises must be a Gas Safe registered engineer" (as of October 2026). The National Careers Service puts it the same way: you need to be on the register to work with domestic gas heating systems.
Gas Safe Register's becoming registered information explains the business side (as of October 2026):
- It is the business that registers, and every engineer doing gas work for it needs current evidence of gas safety competence.
- At least one engineer must hold current evidence when you apply.
- There is an application fee and a registration fee.
- Registration runs for one year and must be renewed.
- Each engineer gets an ID licence card to carry and show customers.
If you only do water, drainage or bathrooms, you don't need Gas Safe. Just don't advertise boiler work you can't legally do.
Step 3: What insurance does a plumbing business need?
One type is compulsory once you hire staff. GOV.UK says you must have employers' liability insurance "as soon as you become an employer", with at least £5 million of cover from an authorised insurer, and you can be fined £2,500 for every day you are not properly insured (GOV.UK, as of October 2026). There are exemptions, for example if you only employ a close family member.
Other policies aren't required by that law, but most plumbers look at them:
Public liability
Damage to a customer's property or injury to the public
Tools and van contents
Theft of tools from the van
Commercial van insurance
Your van, used for business
Professional indemnity
Claims about advice or design, for example heating system design
Income protection
Your earnings if you can't work
Speak to a broker who handles trades. Tell them exactly what you do, including any gas, unvented cylinder or heat pump work.
Step 4: Sole trader or limited company?
Both are common in plumbing. The choice affects tax, paperwork and how you appear to customers.
| Sole trader | Limited company | |
|---|---|---|
| Setup | Register for Self Assessment | Register with Companies House |
| Companies House fee | None, you don't form a company | £100 online or £124 by post |
| Name rules | Can't use "Ltd" or "plc" | Name must be unique at Companies House |
| Admin | Lighter | Annual accounts, confirmation statement, payroll if you pay yourself a salary |
| Liability | You personally | Usually limited to the company |
Sources: GOV.UK register a company and GOV.UK sole trader names, as of October 2026. Companies House says online registrations are usually done within 24 hours.
Many plumbers start as sole traders and incorporate later. Ask an accountant which is better for your numbers; it depends on profit, how you want to pay yourself and plans to hire.
Step 5: How do you register with HMRC?
As a sole trader, GOV.UK says you must register for Self Assessment if you earn more than £1,000 in a tax year (6 April to 5 April). The deadline is 5 October after the end of the tax year you started in. For the 2025 to 2026 tax year, that was 5 October 2026 (as of October 2026).
As a limited company, you register with Companies House, then deal with Corporation Tax and, if you pay yourself through payroll, PAYE.
VAT applies once your taxable turnover goes over £90,000 in the last 12 months, or you expect it to within the next 30 days (as of October 2026). Once registered, the standard rate on most work is 20%.
CIS may apply if you subcontract for builders. GOV.UK lists "installing systems for heating, lighting, power, water and ventilation" as construction work under the scheme, and says unregistered subcontractors have deductions taken at a higher rate (as of October 2026).
Step 6: Choose a name
Pick something short, clear and unique in your area. Check Companies House, the UK trade mark register, domain names and Google Maps before you print anything. Our guide to plumbing business names walks through the checks and gives 70 ideas.
Step 7: What van and tools do you need?
Buy for the work you will actually do first. A plumber starting on repairs and bathroom fits needs a different kit from a gas engineer doing boiler swaps.
A sensible order:
- Van. Big enough for a boiler, a cylinder or a run of pipe, with racking so you can find fittings fast. Get commercial insurance.
- Core hand and power tools. Pipe cutters, benders, grips, press or solder kit, drills, a decent SDS.
- Testing kit. If you do gas, a calibrated flue gas analyser and manometer. Keep calibration certificates.
- Safety kit. PPE, dust control, and a first aid kit in the van.
- Stock. Common fittings and parts so you can finish small jobs on the first visit.
Open a trade account with one or two merchants. Credit terms help cash flow in the first months.
Step 8: How will you quote, invoice and keep records?
Get this right from week one. It is far easier than fixing it at tax time.
GOV.UK lists what every invoice must include: a unique number, your business name and contact details, the customer's name and address, a clear description, the supply date, the invoice date, the amounts, any VAT and the total (as of October 2026).
You have three options:
Free templates.
Our plumbing quote and invoice templates are free spreadsheets with the totals and VAT worked out for you.
Accounting software.
Xero, QuickBooks or similar for invoices and bookkeeping.
Job management software.
Quotes, scheduling, certificates and invoices in one app, linked to your accounts.
If you do gas work, pick software that produces landlord gas safety records and service records on your phone.
Step 9: How do you get your first plumbing customers?
This is where most new plumbing businesses struggle. Here is the order we would do it in.
- Tell everyone you know. Friends, family, old employers, the merchant counter. Your first ten jobs often come from people who already trust you.
- Set up a Google Business Profile on day one. It is free. Pick accurate categories, set your service area, add real photos of your work, and ask every happy customer for a review. Google says prominence, which affects local ranking, includes "how many reviews you have" (as of October 2026).
- Get a simple website. Services, areas covered, your Gas Safe number if relevant, real photos, and a call button on every screen. It does not need to be big at first.
- Consider one lead platform. Checkatrade, MyBuilder, Bark or Rated People can fill gaps while your own channels grow. Track what each job costs you.
- Build repeat work. Boiler services and landlord safety checks come round every year. Set reminders from the first job.
- Never fake reviews. The DMCC Act 2024 bans fake reviews and concealed incentivised reviews, in force since April 2025 (CMS).
When should a new plumber invest in a proper website?
Not necessarily on day one. A free Google Business Profile and word of mouth can carry you through the first months.
The time to invest is when you know which work you want more of (boiler installs, bathrooms, emergency call-outs) and which towns you want it in. That is when a site with proper service and area pages starts to pay.
Our plumbing website design service starts from £1,200 for a sole trader website, built in 2 to 6 weeks from a signed-off brief. You own the domain and the site. If you want to be found in your towns, see local SEO for plumbers, or plumber marketing for the wider plan.
Frequently asked questions
Do I need qualifications to start a plumbing business?
For general plumbing there is no single licence, but customers, insurers and schemes such as WaterSafe expect recognised qualifications. For any domestic gas work, your business must be on the Gas Safe Register by law.
When do I need to tell HMRC I am self-employed?
GOV.UK says you must register for Self Assessment if you earn more than £1,000 from self-employment in a tax year. For the 2025 to 2026 tax year the deadline to tell HMRC was 5 October 2026.
How much does it cost to set up a limited company?
Registering online with Companies House costs £100 and usually takes 24 hours, or £124 by post, as of October 2026.
Do plumbers have to register for VAT?
Only once your taxable turnover goes over £90,000 in a rolling 12 months, or you expect it to within 30 days. You can register voluntarily below that.
Do I need a website to start a plumbing business?
Not on day one, but you do need a Google Business Profile straight away. A simple website with your services, areas, Gas Safe number if relevant and a click-to-call button is worth having within the first few months.
Does the Construction Industry Scheme apply to plumbers?
It can. GOV.UK lists installing heating and water systems as construction work, so if you subcontract for a building contractor, CIS rules may apply to your payments.