Choosing a plumber takes four steps: check the licence, get the price in writing, ask a few questions, and know where to go if the work fails. Plumbing, gasfitting and drainlaying are licensed separately, so check the licence matches the job.
This is general information, not legal advice.
The short version
- Ask to see their New Zealand practising licence and check the expiry date.
- Check the licence covers the work: plumbing, gasfitting or drainlaying.
- Search their licence number on the PGDB public register.
- Ask whether they need supervision and who the supervisor is.
- Get a detailed written quote, not a verbal estimate.
- For gas work, expect a signed gasfitting certificate.
- Keep all certificates and the invoice.
Check the licence
The PGDB’s advice for consumers lists the steps. Ask to see their New Zealand practising licence, either a phone app or a physical licence, and check the expiry date. Confirm it covers the specific work. Then search their licence number on the Board’s public register.
The PGDB’s guide to registration and licence classes separates registration, which happens once when someone qualifies, from the annual licence that authorises restricted work. Certifying is the highest class. Other licence holders and trainees work under supervision, and the supervisor stays responsible. Ask who is supervising any trainee on your job and check them on the register too.
For a step by step walk through, see our guide to checking a plumber, gasfitter or drainlayer.
Get it in writing
Consumer Protection says a quote is generally a confirmed maximum price. An estimate is not fixed and should generally be within 10 to 15 percent. After you accept a quote, the business cannot charge more unless you agree to extra work or the scope of the job changes. It also says an estimate can be verbal or written, with no legal difference, and suggests getting a written quote for expensive jobs. The PGDB also advises getting several written quotes.
If your plumbing job counts as residential building work costing $30,000 or more including GST, the Building Act applies. MBIE’s prescribed checklist says the contractor could be a plumber or electrician as well as a builder. In that case you must get a written contract, and before you sign, the consumer protection standard checklist and a disclosure statement. MBIE’s Do your homework guide (November 2025) also recommends a contract below that line. Most plumbing jobs are well under $30,000, so ask for a detailed written quote that lists the scope, materials, GST and payment terms.
Certificates and consents
For gas work, the PGDB says a certifying gasfitter must provide a signed certificate within 20 working days of the work being connected to the gas supply, and must keep a copy. Store it safely. You may need it when selling, for insurance, or when a gas provider asks for it before supplying gas or refilling LPG bottles. The Board does not hold gas certificates issued after 1 October 2013.
For self-certified plumbing or drainlaying work, the PGDB says to keep the Certificate of Compliance and supporting documents, include the Certificate of Compliance in the Code Compliance Certificate application, and keep the Code Compliance Certificate with your property records. Ask your plumber whether your job needs a consent and who arranges it.
Questions to ask before you say yes
- Can I see your practising licence, and is it current?
- Is that licence for plumbing, gasfitting or drainlaying, and does it fit this job?
- Who is doing the work, and who is supervising?
- Is the price a quote or an estimate, and is GST included?
- What happens if you find something extra? How will it be priced?
- Is a building consent needed, and who arranges it?
- What certificates will I get, and when?
- What guarantee do you give on the work?
Red flags
These are reasons to stop and check. None proves a problem on its own.
- No licence to show, or an expired one.
- A licence for one trade when the job is another.
- They cannot say who supervises.
- No gas certificate after gas work.
- They say no consent or certificate is needed without saying why.
- A verbal price only, or a large deposit. Consumer Protection says not to pay more than 10 percent of the total cost as a deposit.
Your rights if it goes wrong
Consumer Guarantees Act. Consumer Protection lists four service guarantees: reasonable care and skill, fit for purpose, completed in a reasonable time if none was agreed, and a reasonable price if none was agreed. If a problem can be fixed, you can require the business to fix it. If it refuses or delays, you can have it fixed elsewhere and claim the cost, or cancel. For serious failures you can cancel and refuse to pay for the work. You can also claim for further loss caused by the failure.
Building Act. If the work is residential building work, MBIE says implied warranties apply for up to 10 years and there is a 12 month period where defects you report in writing must be fixed.
PGDB complaints. The Board suggests raising the issue with the plumber first. It accepts complaints online or by post, does not accept anonymous ones, and asks for photos, invoices, quotes and compliance documents. It can consider negligent, incompetent or non-compliant work, supervision issues and unauthorised work. It cannot consider billing or contract disputes or refusal to supply gas certificates, and it cannot award compensation or order repairs.
Disputes Tribunal. The Disputes Tribunal handles small claims up to $60,000 and lists poor tradework and disputed charges among the disputes it hears.
How GoodTradie helps
GoodTradie is a free service for homeowners. When you send us a plumbing job, we look the plumber up on the PGDB register before we book them, and we send you one tradie, not several. They give you their own quote and we check it against published NZ figures. That is a guide, not a guarantee. You can still run the checks above yourself. Type your job into the box at the top of the page.
Sources
- PGDB, Advice for consumers (page undated, copyright 2025)
- PGDB, Complaints and disciplinary processes (page undated, copyright 2025)
- PGDB, Understanding registration and licence classes (PDF, undated)
- Consumer Protection, Quotes and estimates (page undated)
- Consumer Protection, Consumer Guarantees Act (page undated)
- Consumer Protection, Poor quality or incomplete work (page undated)
- MBIE, Prescribed checklist (BP 9817, September 2023)
- MBIE, Contractors: Do your homework quick guide (last updated November 2025)
- Disputes Tribunal, What the Tribunal can help with (last updated 20 August 2026)
Need a plumber? See how we find and check one, or type the job in the box at the top.