A name and a number are where checking starts
In Queensland, the QBCC notes that on large jobs where the contractor controls the site, such as new builds, licensed contractors will display a sign with their contact details. When they advertise, licensed contractors there must give their contractor name, matching the name on the licence, and their QBCC licence number.
A name and a number on a sign, an ad or a quote are only the start. Victoria’s Building and Plumbing Commission puts it plainly: an ad, a business card, a quote or someone’s word is not enough on its own, so check a builder’s details before signing a contract or allowing work to start.
This guide covers home building work in general: building a home, extending it or renovating it. Each notice says which state a rule comes from, because the rules are set state by state.
Where to check a builder’s licence
Each register below is kept by that state or territory’s government. Look the builder up yourself, by name or licence number, rather than relying on a printed number alone.
| State or territory | Who keeps it | Where to look |
|---|---|---|
| New South Wales | NSW Government (Verify NSW) | Check a licence on Verify NSW |
| Victoria | Building and Plumbing Commission (BPC) | Find and check a practitioner |
| Queensland | Queensland Building and Construction Commission (QBCC) | QBCC licensee register |
| Western Australia | Building and Energy | Find a registered building service provider |
| South Australia | Consumer and Business Services (CBS) | Find a licence holder |
| Tasmania | Building Standards Tasmania | Find a licensed tradesperson |
| Australian Capital Territory | Access Canberra | Building and construction, then “List of builders” |
The six notices
- 01
Checking a builder’s licence
Each state’s register, what a record shows, and the warning signs regulators name.
- 02
Home warranty insurance
NSW’s HBCF, Queensland’s scheme and Victoria’s Home Warranty, side by side.
- 03
Deposits and progress payments
The deposit caps in four states, and paying only for stages that are finished.
- 04
The building contract
What a written contract must contain in NSW and Queensland, and the cooling-off period.
- 05
Variations
How a change to the work is agreed and written down before it is done.
- 06
Defects and disputes
Statutory warranties, time limits and the dispute services in three states.
Four numbers to know, in three states
The thresholds that decide when you need a written contract and warranty insurance, how much deposit a builder may ask for, and how long you have to change your mind.
| The rule | NSW | Victoria | Queensland |
|---|---|---|---|
| Written contract needed | Over $5,000 including GST | A major domestic building contract for work involving more than one trade and worth more than $10,000 | Work valued at more than $3,300 |
| Largest deposit | 10% | 10% under $20,000; 5% at $20,000 or more (changing by 1 December 2026; see the note below) | 20% at $3,300 or less; 10% from $3,301 to $19,999; 5% for $20,000 or more (Level 2) |
| Warranty insurance required | Most residential building work over $20,000 | Eligible work over $20,000, under contracts signed on or after 1 July 2026 | Residential construction work over $3,300 |
| Cooling-off | Five clear business days, for contracts over $20,000 | Five days to change your mind after signing, which Consumer Affairs Victoria says you no longer have if you get independent legal advice before you sign | Generally five business days, for contracts over $3,300 |
Victoria passed new building contract laws in September 2025 that take effect by 1 December 2026 and may change the Victorian deposit limits, payment stages and contract rules in this table. Until then, Consumer Affairs Victoria says the current laws remain the same. Check Consumer Affairs Victoria before you sign.
From the first quote to the last payment
- Before you choose
Look the builder up on your state’s register. In Victoria, the BPC’s search shows whether a registration or licence is current, what type of work it allows and whether it has any conditions or limits. Notice 01
- Before you sign
Read the whole contract. In NSW, builders must give you the Consumer Building Guide before a contract for residential building work over $5,000. Notice 04
- Before you pay a deposit
See the insurance certificate. NSW’s advice is not to pay the deposit until you have seen your contractor’s insurance certificate and checked it is valid; Consumer Affairs Victoria says to hold the deposit back until the builder hands you a certificate of currency for your property. Notice 02 and notice 03
- While the work goes on
NSW’s advice is that progress payments should match work actually done, not time on the job. In Queensland, a contractor must give you a variation in writing before the variation work starts, unless it is urgent and that is not reasonably practicable. Notice 05
- After the work is finished
In NSW, statutory warranties last six years for major defects and two years for all other defects, from the date the work was completed. Other states set their own periods. Notice 06