Reference dates, payment due dates and adjudication timeframes across QLD, NSW, VIC and SA — business-day aware, public-holiday accurate.
Calculations for QLD, NSW, VIC and SA in one place. Each state's SOP Act uses different timeframes — the calculator applies the right rules for your jurisdiction automatically.
Weekends and public holidays are excluded where the relevant Act requires business days. State and territory public holiday calendars are built in.
Reference date, payment due date, payment schedule deadline, adjudication application windows, adjudicator response deadline — mapped in a single timeline.
Select your jurisdiction and contract type, enter the reference date or the date you served your payment claim, and Sopal maps every downstream deadline onto a calendar — so you can see at a glance when the respondent must pay, when they must provide a schedule, and how long you have to apply for adjudication.
Security of payment legislation creates a chain of dates that determines whether a payment claim is valid, when money must be paid, and how long parties have to exercise their rights. Missing any link in that chain can result in a claim becoming invalid, a right to adjudicate being lost, or a respondent being held to a scheduled amount they may have disputed if they had acted in time. Understanding the concepts below is the starting point for using the calculator effectively.
Note: this page is general information only and is not legal advice. Timeframes under the SOP legislation differ between jurisdictions and have been amended over time — always confirm the current provisions of the Act that applies to your contract before relying on any date.
A payment claim under SOP legislation must be made on or after a "reference date". The reference date is the trigger that determines when a claimant is entitled to make a progress claim. It does not have to be the date the claim is actually served — a claimant can serve later — but a claim served before a reference date arises may not be a valid payment claim.
Reference dates are generally set by the construction contract. If the contract specifies a date each month on which progress claims may be made (for example, the last business day of the month, or the 25th), those are the reference dates. If the contract does not adequately provide for reference dates — or there is no written contract — the SOP legislation provides a default. In Queensland under the Building Industry Fairness (Security of Payment) Act 2017 (the "BIF Act"), for example, the default is the last day of each named month in which construction work is carried out or related goods and services supplied. Defaults in other states differ, so always check the Act that applies.
The reference date matters for the calculator because it anchors the entire payment timeline. Everything else — when the claim must be served, when the respondent must respond, when the claimant may apply for adjudication — flows from it.
Once a valid payment claim is served, the respondent has a defined period to pay the claimed amount (or the scheduled amount, if a payment schedule has been provided). If neither the contract nor the relevant Act provides otherwise, the SOP legislation in each state specifies a maximum time for payment after the date of service of the payment claim. That period differs by state and, in some jurisdictions, by whether the contract is a head contract or a subcontract.
If the respondent does not pay by the due date, the claimant generally has the right to suspend work (subject to notice requirements), to apply for adjudication, or to recover the debt through a court. The due date for payment is therefore a hard deadline that both sides need to track carefully.
In most Australian SOP regimes, if a respondent intends to pay less than the claimed amount — or to dispute any part of the claim — they must provide a payment schedule within the timeframe allowed by the relevant Act. A payment schedule must identify the scheduled amount the respondent proposes to pay and must state the reason for withholding any amount.
The consequences of failing to provide a payment schedule on time are severe: in most jurisdictions the respondent becomes liable to pay the full claimed amount and loses the right to raise any reasons in adjudication (or court proceedings) for withholding payment. The schedule deadline is therefore often the most time-critical date for a respondent.
The time allowed to provide a payment schedule differs between states and can also be affected by the contract. Some jurisdictions run the clock from the date of service of the payment claim; others run it from another trigger. Always confirm the current Act for your jurisdiction.
If a payment schedule is not provided, or if the respondent schedules less than the claimed amount, the claimant may apply for adjudication. However, the right to apply for adjudication is time-limited — there is a window that opens after specified preconditions are met and closes after a prescribed number of days.
In Queensland under the BIF Act the adjudication application window rules differ depending on whether the respondent failed to provide a schedule at all, provided a schedule for a lesser amount, or failed to pay a scheduled amount. The window in each case is counted from different trigger events. NSW, VIC and SA each have their own window rules that do not necessarily mirror Queensland. The key point is that once the adjudication application window closes, the right to adjudicate that payment claim is lost — a significant consequence that can rarely be reversed.
The Sopal calculator identifies the opening and closing dates of the adjudication window based on the facts you enter, so you can see clearly how much time remains to file.
Once an adjudication application is accepted by an authorised nominating authority (ANA) and an adjudicator is appointed, the adjudicator has a prescribed period to determine the application. The respondent also typically has a period to lodge an adjudication response. These periods are set by the relevant Act and are tracked in the Sopal timeline, though they are downstream of the application itself and are included for planning purposes.
This is one of the most common sources of error in SOP date calculations. Some timeframes in the SOP legislation are expressed in calendar days; others are expressed in business days. Business days typically exclude weekends and public holidays in the relevant state. Getting this wrong — treating business days as calendar days, or miscounting a public holiday — can result in a party believing they have more time than they actually do.
The Sopal calculator applies the correct day-counting rule for each timeframe in each jurisdiction, using up-to-date public holiday data for QLD, NSW, VIC and SA. If a deadline falls on a weekend or public holiday, the calculator identifies when the effective deadline occurs. You should always confirm the current position under the relevant Act, as legislation can be amended.
The SOP Acts set minimum entitlements and maximum timeframes that generally cannot be contracted out of to the detriment of the claimant. However, contracts can and do provide for shorter payment periods, different reference date schedules, and other variations within the limits the legislation allows. The calculator prompts you for the contract-specified payment period where relevant so that it can apply the earlier of the contractual and statutory dates — because in practice, whichever produces the earlier due date may be the operative deadline.
Always read your contract alongside the applicable SOP Act and, where the stakes are significant, take advice from a construction lawyer.
As well as the timeline, the calculator surfaces a compliance checklist — showing which steps have been completed, which are upcoming and which are at risk — so you can use it to brief a team or review a matter quickly.
The four states covered by the Sopal Due-Date Calculator each have their own SOP Act. The table below gives a high-level guide to the relevant legislation. Timeframes and rules change — always confirm the current Act for your jurisdiction and your contract.
| State | Legislation | Key feature |
|---|---|---|
| Queensland | Building Industry Fairness (Security of Payment) Act 2017 (BIF Act) | Project bank accounts for certain contracts; head contractor / subcontractor distinction in payment timeframes; adjudication under an ANA |
| New South Wales | Building and Construction Industry Security of Payment Act 1999 | One of the oldest and most litigated SOP regimes in Australia; broad claimant base; payment schedule regime with strict consequences for non-service |
| Victoria | Building and Construction Industry Security of Payment Act 2002 | Similar structure to NSW; separate timeframes; "second chance" notice regime applies in some circumstances before adjudication |
| South Australia | Building and Construction Industry Security of Payment Act 2009 | Later-vintage legislation informed by eastern-state experience; covers a broad class of construction contracts |
Western Australia, the Northern Territory and the ACT each have their own SOP frameworks and are not currently covered by the Sopal calculator. If your project is in one of those jurisdictions, consult the relevant legislation directly or seek advice from a construction lawyer.
The SOP Acts were enacted at different times by different parliaments, and each reflects the policy choices made at the time of enactment and subsequent amendment. As a result, even for the same step in the process — say, the time a respondent has to provide a payment schedule — the number of business or calendar days allowed can differ materially between QLD, NSW, VIC and SA. Practitioners who work across multiple jurisdictions must not assume that a timeframe they know well from one state applies in another. The Sopal calculator removes that guesswork by applying the correct rules for each jurisdiction you select.
Know exactly when your payment claim is due, when the head contractor must respond with a schedule, and — critically — when your adjudication application window opens and closes, so you don't inadvertently let a right expire.
Track the payment schedule deadlines you must meet on claims from below and the dates by which you must pay scheduled amounts — avoiding the severe consequences of missing those deadlines under the SOP Acts.
Monitor payment obligations under head contracts across multiple projects, and understand the chain of dates that flows from each payment claim served against your contract.
Certify payment amounts with confidence and brief project teams on upcoming SOP deadlines — across multiple jurisdictions if your practice operates in more than one state.
Quickly map a matter's timeline and cross-check date calculations when advising clients or reviewing whether rights have been exercised in time. Pair with AI case-law research and adjudicator statistics for a full matter view.
Once you know your payment due date, the Sopal Interest Calculator works out the interest accruing on unpaid amounts from that due date to the date of payment or judgment. Interest under the SOP Acts and related regulations accrues at rates prescribed by legislation — the calculator applies the correct rate for your jurisdiction and compounds or simple-rates the amount as the relevant Act requires. Use the two calculators together to quantify the full amount recoverable on an overdue payment claim.
A reference date is the date on or after which a claimant becomes entitled to make a progress payment claim under the SOP legislation. It is usually set by the construction contract — for example, the last business day of each month, or the 25th of each month. If the contract does not adequately provide for reference dates, the relevant Act provides a default. A payment claim served before a reference date arises may not be a valid payment claim, which can have serious consequences for adjudication. The Sopal calculator helps you confirm when your next reference date falls so you know the earliest date you can validly serve your claim.
The consequences of failing to provide a payment schedule within the prescribed time are among the most significant under the SOP Acts. In most jurisdictions, a respondent who fails to provide a timely payment schedule becomes liable to pay the full claimed amount and loses the right to raise any reasons for withholding payment in subsequent adjudication or court proceedings. The exact consequences differ by jurisdiction and the specific circumstances of the claim, so always confirm the position under the Act that applies to your contract. The Sopal calculator shows the payment schedule deadline clearly so respondents can act in time.
The adjudication application window — the period during which a claimant may lodge an adjudication application — opens and closes based on trigger events and day-counts set out in the relevant Act. The triggers and counts differ depending on the circumstances: whether the respondent failed to provide a payment schedule at all, provided a schedule for a lesser amount, or failed to pay a scheduled amount. They also differ between jurisdictions. The Sopal calculator maps the open and close dates of the window based on the facts you input. Because missing the window means losing the right to adjudicate that claim, tracking this date carefully is critical.
It depends on the timeframe and the jurisdiction. Some periods under the SOP Acts are expressed in business days (excluding weekends and public holidays); others are expressed in calendar days. The Sopal calculator applies the correct day-counting rule for each specific timeframe, using up-to-date public holiday calendars for QLD, NSW, VIC and SA. Where a deadline falls on a weekend or public holiday, the calculator flags the effective deadline date. If you are calculating dates manually, always confirm whether the relevant provision uses business days or calendar days, as the difference can be material.
You select the jurisdiction — QLD, NSW, VIC or SA — when you set up a calculation, and the calculator applies the rules for that state's SOP legislation automatically. If you work across multiple states, you can run separate calculations for each jurisdiction. The calculator does not blend rules between states or ask you to know the correct timeframe yourself — that logic is built in. Always confirm that the calculation reflects the current version of the Act, as legislation can be amended.
Yes, within limits. The calculator prompts you for the contractually specified payment period where relevant, because a contract can provide for a shorter payment period than the statutory maximum (subject to the limits the Act places on contracting out). Where you enter a contract payment period that is shorter than the statutory default, the calculator will apply the earlier date as the operative payment due date. For payment schedule timeframes, the contract may also have something to say — enter your contract details and the calculator will flag where the contract provision may be more onerous than the Act alone.
No. The Sopal Due-Date Calculator is a practical tool to help you understand and track SOP deadlines — it is general information, not legal advice. Timeframes under the SOP legislation can be affected by the specific terms of your contract, how and when the payment claim was served, whether the claim is a valid payment claim under the Act, and other facts specific to your matter. Where the stakes are significant, or where you are unsure whether a right has been validly exercised or has expired, you should seek advice from a construction lawyer. Sopal's Research product — including AI-assisted case-law search and Queensland adjudication decisions — is available to support legal professionals working on these matters.
Not currently. The Sopal Due-Date Calculator covers QLD, NSW, VIC and SA. WA, the ACT and the NT each have their own SOP frameworks and are not yet supported. If your project is in one of those jurisdictions, consult the relevant legislation directly or seek advice from a construction lawyer familiar with that jurisdiction's SOP regime.
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