Navigating the Pitfalls: Common SOPA Mistakes to Avoid (Part 5 of Our SOPA Series)

Welcome back to our series on the Security of Payment Act (SOPA). In our last post, we navigated the fast-paced world of adjudication. We saw how SOPA provides a powerful mechanism for resolving payment disputes swiftly. However, this speed and rigidity mean that procedural missteps can have significant and costly consequences.
The Act is unforgiving of errors. A simple mistake in timing or content can derail a valid claim or leave a respondent with a hefty, indefensible bill. Today, we're flagging the most common pitfalls we see in practice. Being aware of these traps is the first step to avoiding them, whether you are the one making a claim or the one responding to it.
Here are some of the most common mistakes made by parties using the SOPA regime.
The Defective Payment Claim
The entire SOPA process begins with the payment claim. If this initial document is invalid, the whole process can collapse.
Common errors include:
🔍Failure to Identify as a SOPA Claim: The claim must explicitly state that it is made under the relevant Security of Payment Act. This simple sentence is non-negotiable.
📑Insufficient Detail: The claim must clearly identify the construction work or related goods and services to which the progress payment relates. A vague, lump-sum figure without adequate breakdown or reference to the contract may be deemed invalid.
❌Incorrect Service: The claim must be served on the person specified in the contract or as otherwise required by the Act. Sending it to the wrong person or address can render it ineffective.
Missing the Clock: Fatal Timing Errors
As we stressed in Part 4, SOPA runs on a stopwatch. For a claimant, missing a deadline is often fatal to the claim for that reference period. Key timing mistakes include:
🔨Lodging an Adjudication Application Too Early or Too Late: The window to apply for adjudication is strict and varies depending on whether a payment schedule was provided and the amount paid. Applying even one day outside this window will result in the application being rejected.
⏰Waiting Too Long After Work is Complete: SOPA has time limits for serving a final payment claim after the completion of work under the contract.
The Under-Prepared Adjudication Application
When a dispute proceeds to adjudication, the application is the claimant's primary opportunity to plead their case. A common mistake is to submit a sparse application, assuming the adjudicator will investigate or fill in the blanks. The application must be a comprehensive, self-contained package including:
🔵All relevant contractual documents.
🔵Evidence of the work performed (photos, delivery dockets, signed day sheets).
🔵Detailed submissions explaining why the amount is owed.
An adjudicator can only decide based on the information provided. What you leave out cannot be considered.
Mistakes Primarily Made by Respondents
- Ignoring a Payment Claim
This is arguably the biggest and most costly mistake a respondent can make. If a respondent fails to provide a payment schedule within the statutory timeframe (typically 10 business days), they become liable to pay the entire amount claimed by the claimant, regardless of any genuine disputes or defects. - The Inadequate Payment Schedule
Almost as bad as providing no schedule is providing a defective one. To be valid, a payment schedule must:
🔵Identify the payment claim it is responding to.
🔵State the amount of the payment (if any) that the respondent proposes to make (the "scheduled amount").
🔵If the scheduled amount is less than the claimed amount, it must state all reasons for withholding payment. Vague statements like "work is defective" are insufficient. The reasons must be specific enough for the claimant to understand the basis of the dispute. - The "New Reasons" Trap
This is a crucial point that many respondents misunderstand. In an adjudication response, a respondent is generally barred from introducing any new reasons for withholding payment that were not first included in their payment schedule.
This makes the payment schedule the single most important document for a respondent. A failure to list a reason at that early stage means you lose the right to argue it before the adjudicator.
Universal Pitfalls for Both Parties
🔵Poor Record Keeping: SOPA disputes are won and lost on evidence. Parties who fail to maintain meticulous records—daily logs, site diaries, photographic evidence, variation approvals, and clear written communications—are at a significant disadvantage. Think of your documentation as your armour; without it, you are exposed.
🔵Going it Alone: While SOPA is designed to be more accessible than the courts, its technical requirements and strict deadlines create a minefield for the inexperienced. The cost of professional legal advice to ensure compliance is often a fraction of the amount that could be lost through a procedural error.
SOPA is a powerful tool, but it demands respect for its strict processes. Diligence, attention to detail, and a clear understanding of the rules are the keys to using it effectively and avoiding its many pitfalls.
In our next and final post in this series, we will cover the last step in the process: Enforcement. We'll explore what happens when a party fails to comply with an adjudicator's determination and the steps a successful claimant can take to recover the money they are owed. Stay tuned!

Senior Solicitor
Email: kristen@hntlegal.com.au









