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SOP Act 1999 (NSW): the cashflow law every NSW builder needs to know

NSW Security of Payment Act 1999: payment claims, fast-track adjudication, retention trust, 2021 owner-occupier inclusion, 2024 unlicensed-builder exclusion.

By Dan Waring. Last updated 15 May 2026. Verified 15 May 2026.

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In plain English

The Building and Construction Industry Security of Payment Act 1999 (NSW), known across the industry as SOPA, is the law that gives a contractor on a NSW construction project a statutory right to make a progress payment claim and a fast-track adjudication route if the claim is not paid. SOPA does not care whether the contract is written, verbal or implied, and (since 1 March 2021) does not care whether the project is commercial or residential owner-occupier. If you are doing construction work in NSW and someone owes you money for it, SOPA is the lever.

The two things that make SOPA different from suing in court for a debt:

  1. It is fast. A payment claim under s.13 triggers a payment schedule under s.14 within 10 business days. If the response is missing or short, an adjudication application under s.17 can be lodged, and a determination is typically delivered within 10 to 30 business days. Court recovery for the same debt routinely runs 6 to 24 months.
  2. Adjudication binds for cashflow. The adjudicator’s determination is enforceable as a judgment debt. The respondent can later sue to recover what was paid if the merits are against them, but they pay first and argue second. This is intentional: SOPA is the cashflow protection statute, not the final-determination statute.

What it requires

For a builder running NSW jobs, SOPA imposes (and grants) the following:

  1. Right to make a payment claim under s.13 on each reference date in the contract (commonly monthly). The claim must:
    • Identify the work it covers.
    • State the claimed amount.
    • On head contracts, attach a supporting statement under s.13(7) declaring that all subcontractors have been paid for that period (false declaration is a corporate offence).
  2. Obligation to respond to a payment claim under s.14 within 10 business days (or sooner if the contract specifies). The response is a payment schedule that either accepts the amount, schedules part of it, or sets out reasons for withholding.
  3. Right to adjudicate under s.17 if the payment schedule is short, late or missing. The adjudication application names the dispute, lodges with an Authorised Nominating Authority (ANA), and runs to a binding determination.
  4. Trust obligations on retention money on projects over $20m under s.12A and the Building and Construction Industry Security of Payment Regulation 2020: retention amounts must be paid into a dedicated trust account at an authorised deposit-taking institution. See retention trust mechanism for the cross-state picture.

What it doesn’t cover

  • Unlicensed or uninsured residential builders. From 20 August 2024 (verified 2026-05-15), s.8(2) was amended so that a residential builder operating without a Home Building Act licence or without home warranty insurance has no SOPA rights. The right to progress payment under SOPA is extinguished if the work is residential and the contractor is unlicensed or uninsured. The contractor is left to sue in court for a debt, with the licensing breach as a defence available to the respondent. Check your licence status on NSW Fair Trading before you lodge a SOPA claim on residential work.
  • Final determination of contract merits. SOPA is interim. An adjudication determination can be revisited in court; the cashflow effect is binding, but the contractual rights are not finalised until the court resolves them or the parties accept the SOPA outcome.
  • Disputes that are not payment claims. SOPA is for “what am I owed for the work done in this period”. Variation disputes are within scope only to the extent the claim quantifies a payment. Pure design liability, defects in completed work, or contract-formation disputes go to mediation, adjudication under the contract, or court.
  • Operational construction in Victoria, Qld, WA, SA, Tas, NT and ACT. Each has its own SOP Act with similar structure but different time limits, ANA panels and procedural rules. Cross-jurisdictional projects need to identify the governing Act for each contract.

Practical implications

  • Owner-occupier residential work is in scope from 1 March 2021 (verified 2026-05-15). Before that date the residential exemption made SOPA unavailable on most family-home jobs. After that date, a builder on a kitchen extension or a knockdown-rebuild can use SOPA to recover an unpaid progress claim. This was the single biggest practical change to residential-builder cashflow in twenty years.
  • The licensing check on 20 August 2024 changes the math. Before that date, an unlicensed contractor could in theory still lodge a SOPA claim and win adjudication; after that date, the claim has no statutory foundation. Builders contracting under any residential rebadge (e.g. a different entity) need to confirm the licensed entity is the contracting party, otherwise the SOPA right vanishes on the day of breach.
  • Section 13(7) supporting statement is non-negotiable on head contracts. A head contractor lodging a payment claim must attach a written declaration that all subcontractors are paid. False statements are an offence; in practice, a missed supporting statement is the most common procedural defect that defeats an otherwise valid claim.
  • Adjudication is not free. Adjudicator fees are typically split between the parties, often defaulting to the respondent if the determination favours the claimant. Budget $5,000 to $25,000 in fees on a typical residential adjudication; commercial disputes can run materially higher.
  • Use the contract’s contractual claim mechanism as the first step. SOPA sits over the top of the contractual claim regime. Issue the contractual progress claim; if unpaid, escalate to a SOPA payment claim. Skipping the contractual step is procedurally weaker and signals adversarial intent earlier than necessary.

References

See also

Last updated: 2026-05-15. Verified: 2026-05-15. Quarterly review for currency.

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