Claiming for Variations Under the Security of Payment Legislation

You’ve done extra work on site. The head contractor agreed to it (or so you thought). Now they’re dragging their feet on payment, or worse, denying it was authorised. Variations are a common flashpoint in construction, and the good news is that Australia’s Security of Payment legislation gives you a practical way to force the issue. The bad news? You need to get it right.

This guide walks you through claiming for variations under the SOP laws in your state.

What counts as a variation?

A variation is work outside your original contract scope. It could be:

• Additional labour or materials the contractor asked you to supply
• Changes to the specification or method of work
• Work caused by errors in the original design or documentation
• Delays or disruptions beyond the original program

The key thing: there has to be some change to what you were originally asked to do. If it’s work you already contracted for, it’s not a variation—it’s just part of your original claim.

The tricky part isn’t what a variation is. It’s what you can prove. The head contractor will often say they never authorised extra work, or that it was included in the original price. If there’s no written agreement, you’re relying on emails, text messages, site notes, or even a conversation with the site supervisor. That evidence matters, so keep it safe.

How security of payment legislation treats variations

Australia’s SOP Acts—like the NSW Security of Payment Act 1999, QLD Building Industry Fairness Act 2017, VIC Security of Payment Act 2002, and equivalents in other states—don’t carve out special rules for variations. They just say you have the right to serve a payment claim for work done. A variation claim is still a payment claim.

What matters is:

1. You describe the work clearly (what, when, where, how much)
2. You include the amount claimed for that variation
3. You serve it on the right person (usually the head contractor or principal)
4. You meet the deadline—usually within a set timeframe after the work is complete (this varies by state and contract type)

Once you’ve served a valid claim, the respondent has a statutory window to issue a payment schedule (typically 10 business days in NSW, 5 business days in QLD). If they don’t, or if their payment schedule offers you less than you claimed, you can apply for fast-track adjudication.

The SOP laws don’t require the respondent to have already agreed in writing that a variation exists. They just need to respond to your claim. So even if the head contractor is denying the work was authorised, your claim forces them to take a position in writing and triggers the adjudication pathway if they refuse to pay.

Building your variation claim

A solid variation claim needs:

• A clear description of the work — what you did, not just “extra stuff”. Include dates if you can.
• A breakdown of cost — labour, materials, plant, anything specific to that variation. Don’t just lump it in with your base claim.
• Evidence it was requested — an email, a text, a site instruction, a meeting note. Anything showing the head contractor or site supervisor asked you to do it.
• The contractual basis — if your contract has a variation procedure, follow it (e.g., written variation orders, site manager approval). The SOP Act doesn’t override your contract; it supplements it.

You can include a variation claim as part of a progress claim, or serve it separately. Most tradies bundle it into their next progress claim with a clear line item flagged as “Variation – Description”.

If the variation is disputed, don’t try to hide it or bury it. Make it obvious. That way, when you serve the claim and the head contractor responds, they can’t later claim they didn’t know what you were asking for.

Serving the claim and what happens next

Your payment claim (including any variation) must be served correctly. Check your state’s SOP Act for the exact rules, but generally:

• Serve it on the head contractor or whoever your contract says to serve it on
• Keep proof of service (email read receipt, registered post, hand delivery, or statutory declaration)
• Serve it within the deadline set by your contract or the SOP Act (or within a reasonable time if the contract is silent)

Once served, the head contractor has a set number of business days to respond with a payment schedule. If they don’t respond, or if their payment schedule doesn’t match your claim amount, you can push for adjudication. That’s a faster, cheaper way to get a decision than going to court, and it’s built into the SOP laws across all states.

Many debtors choose to pay or settle rather than face an adjudication, because the process is quick and the adjudicator’s decision is binding (though they can dispute it in court later on narrow grounds).

If you’re uncertain about how to structure a claim or what evidence you need, PayClaim’s self-service platform walks you through the process for your state and lets you file a payment claim for a flat fee of AUD $79. You don’t need a lawyer to use it.

Bottom line

Variations are legitimate. They happen on almost every job. The Security of Payment legislation exists to make sure you’re not left hanging because someone forgot to agree it in writing or decided to backpedal later. If you’ve done the work and can point to some evidence it was asked of you, you have grounds to claim it. Get it down in writing, serve it properly, and let the SOP process do the rest.