What Is a “Reference Date” in the Australian Security of Payment Act (and Why It Matters)?

If you’re a subcontractor or tradie chasing unpaid money from a builder or head contractor, the Security of Payment Act in your state is your fastest legal pathway to recover it. But there’s a technical gotcha that kills claims before they’re even lodged: the reference date.

Most tradies don’t understand what a reference date is, how to calculate it, or why it matters. Get it wrong, and your payment claim can be rejected—even if you’re owed legitimate money. This guide breaks down exactly what a reference date is, why it’s critical, and how to use it correctly when you file a payment claim online.

What exactly is a “reference date” under the Security of Payment Act?

A reference date is the cut-off date that defines which work, labour, materials, and costs you can include in your payment claim. It is not the date you submit your claim, and it’s not the date work was completed.

The reference date is a statutory concept written into every state and territory’s Security of Payment legislation. It marks the last day of the period to which your claim relates. Any work, goods, or services provided after the reference date cannot be included in that claim.

Think of it this way: if you lodge a claim with a reference date of 30 April 2024, you can only claim for work done up to and including 30 April. Work completed on 1 May onwards belongs in a later claim.

How is the reference date calculated?

The reference date is calculated backwards from the date you actually lodge (serve) your payment claim, using a statutory formula. The exact formula depends on which state or territory you’re in.

In most jurisdictions, the reference date is calculated as follows:

• Work out how long the payment period was. This is the period covered by your claim (e.g. 28 days, one calendar month, or the full contract period).
• Count backwards from the lodgement date. The reference date sits at the end of the most recent complete payment period before you submit your claim.
• Account for any agreed contract variations. The contract may specify a different reference date calculation; if so, use that instead.

Here’s a worked example:

You lodge a payment claim on 15 May 2024. Your contract specifies monthly payment periods (1st to the last day of each month). The most recent complete monthly period is 1 April to 30 April 2024. Your reference date is therefore 30 April 2024. Any work done from 1 May onwards must go in a later claim.

If you had instead lodged on 10 May, the most recent complete period would still be 1–30 April, so the reference date would still be 30 April.

How does the reference date differ across Australian states and territories?

While the principle of a reference date is consistent across Australia, each state and territory’s Security of Payment Act defines it slightly differently. The statutory formulas vary, and some jurisdictions offer more flexibility than others.

Key takeaway: Don’t assume the reference date is the same in every state. Check your contract first—it may specify a custom reference date. If not, apply your jurisdiction’s statutory default.

Why does the reference date matter so much?

The reference date matters because it defines the legal scope of your claim. Here’s why that’s critical:

1. Determines what you can claim. Only work and costs up to the reference date are included. Work after that date is excluded.
2. Affects claim validity. If your reference date is calculated wrongly or too far in the past, a respondent (the builder or head contractor) can reject your claim as invalid under the Act.
3. Triggers statutory deadlines. Once you lodge a claim with a stated reference date, the respondent has a set time to respond with a payment schedule (typically 10 business days under NSW law, for example). The reference date locks in that timeline.
4. Prevents double-claiming. The reference date ensures you don’t accidentally claim the same work twice in multiple claims.
5. Required by the Act. Your payment claim must state the reference date. If you don’t, it may be rejected as non-compliant.

What happens if you get the reference date wrong?

If your reference date is calculated incorrectly or stated wrong on your claim, the respondent can reject it as invalid. Many builders will do exactly this—it’s one of the easiest technical grounds to dispute a claim.

For example, in NSW, section 13(2) of the Building and Construction Industry Security of Payment Act 1999 requires that a payment claim state the reference date. If it doesn’t, or if the date is inconsistent with the Act’s rules, the respondent can serve a notice of non-compliance.

This doesn’t mean you lose the money you’re owed—you can re-lodge a corrected claim. But it delays payment and costs you time and frustration.

Some common mistakes:

• Claiming work done after the reference date.
• Setting a reference date too far in the past (e.g. claiming a six-month period when the contract specifies monthly periods).
• Not updating the reference date correctly on subsequent claims.
• Confusing the reference date with the lodgement date or invoice date.

How do you work out the correct reference date for your next claim?

Follow this step-by-step process:

1. Check your contract. Does it specify a payment period (e.g. monthly, fortnightly, 28 days)? If yes, use that period.
2. Identify the most recent complete period. If your contract says monthly periods (1st to the last day of each month), and today is 15 May, the most recent complete period is 1–30 April. The reference date is 30 April.
3. Check your jurisdiction’s rules. Look up the relevant Act for your state or territory (see table above) to confirm how the reference date formula applies if no contract term exists.
4. Document the date clearly. When you lodge your claim, make sure the reference date is stated explicitly and matches your calculation.
5. Keep a record. Note the reference date used in each claim so you don’t accidentally use the same one twice or leave a gap.

If you’re unsure, it’s better to ask your head contractor or lawyer than guess. A wrong reference date can invalidate your claim.

Can you change or dispute the reference date once a claim is lodged?

No, not easily. Once you lodge a claim with a stated reference date, that date is locked in for the purposes of that claim. The respondent then has a statutory obligation to respond (usually within 10 business days).

If you lodge a claim and then realize the reference date is wrong, you’ll need to withdraw it and submit a corrected claim with the correct reference date. This delays everything and may damage your credibility.

The only exception is if the respondent serves a notice of non-compliance (which they can do if the reference date breaches the Act), in which case you have a set time to correct and re-serve the claim. But this is reactive, not ideal, and costs you time.

How does the reference date affect your payment timeline?

The reference date triggers statutory timeframes. Here’s the general flow:

1. You lodge a claim with a reference date (e.g. 30 April 2024).
2. The respondent has a set time to issue a payment schedule (10 business days in NSW, for example). If they don’t, they become liable to pay the full amount claimed.
3. If the respondent disputes the claim, you can apply for adjudication—a fast-track dispute resolution process under the Act.
4. The adjudicator must make a determination within a set timeframe (typically 10–15 business days, depending on the jurisdiction).

A correctly calculated reference date ensures these timeframes are triggered properly. A wrong one gives the respondent grounds to say your claim is invalid and doesn’t trigger the deadlines at all.

What if your contract doesn’t specify a payment period?

If your contract is silent on payment periods, each state and territory has a statutory default. For example:

• NSW: The reference date is the last day of the month in which the claim is made (unless you specify otherwise in the claim itself).
• Victoria and Queensland: The reference date is at least 1 day after the date of the last claim.
• South Australia and ACT: The default is typically 28 days before lodgement.

Check your state’s Act to find the exact rule if no contract term applies.

Should you get help calculating the reference date?

If you’re lodging a straightforward monthly claim and your contract specifies monthly periods, calculating the reference date is simple. But if your contract is complex, your payment periods are irregular, or you’re in a multi-state dispute, it’s worth getting it right from the start.

Many builders will scrutinize the reference date looking for a reason to reject your claim. The safer option is to double-check before you lodge—or use a tool designed to guide you through the claim process, which will prompt you to state and verify the reference date as part of the submission.

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Frequently Asked Questions

Q: Is the reference date the same as the date I lodge my claim?

No. The reference date is the cut-off date for the work period you’re claiming for. The lodgement date is when you actually submit the claim to the respondent. The reference date is always earlier than (or at most equal to) the lodgement date. For example, you might lodge a claim on 15 May for work done up to 30 April (reference date = 30 April).

Q: Can I include work done after the reference date in my payment claim?

No. Any work, materials, or services provided after the reference date cannot be included in that claim. You must lodge a separate claim in a future period to cover work done after the reference date. This prevents you from including work that falls outside the defined period.

Q: What happens if I get the reference date wrong on my claim?

The respondent (builder or head contractor) can reject your claim as invalid under the Security of Payment Act. You’ll then need to lodge a corrected claim with the correct reference date. This delays your payment and gives the respondent a technical ground to dispute you, even if the work and costs are legitimate.

Q: Do all Australian states use the same reference date formula?

No. While the concept is the same across Australia, each state and territory’s Security of Payment Act defines the reference date slightly differently. Some default to monthly periods, others to 28 days. Always check your contract first, then your jurisdiction’s legislation to confirm the correct rule applies to your claim.

Q: Can the builder or I change the reference date after the claim is lodged?

Not after lodgement. The reference date is set the moment you serve the claim. If it’s wrong, you must withdraw that claim and lodge a new one with the correct reference date. The respondent cannot unilaterally change it either—but they can reject your claim if the reference date breaches the Act’s rules.

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