Serving a payment claim under the SOP Act
On a Singapore project the payment claim is not a courtesy. It is the document that fixes the amount in dispute, starts the response clock, and opens the door to adjudication if the money does not arrive.
QScope Team · 2 April 2026 · 6 min read
The Building and Construction Industry Security of Payment Act, the SOP Act, gives a contractor in Singapore a statutory right to serve a payment claim and to be paid the claimed amount unless the respondent answers it properly. Everything that follows in the cycle, the payment response, the due date, the right to adjudicate, hangs off that one document and the date it was served.
What a payment claim has to do
A payment claim states the amount the claimant says is due for work done or goods supplied up to the reference date, and it identifies that work. It is cumulative. You value everything carried out to date, gross, then the claim for the cycle is the difference from the last claim.
- The amount claimed. The gross value to date, less what has already been claimed, expressed as a single figure the respondent can accept or answer.
- The work it covers. Enough detail that the respondent can value each element, not a single lump with no breakdown.
- The reference date. The date, set by the contract, that entitles the claimant to make the claim for that cycle.
Serve it, and record that you served it
The response clock and the due date both run from service of the payment claim, so the service date is not administrative detail. It is the reference point for every deadline in the cycle. Serve the claim in the manner the contract requires, and keep proof of when it went and to whom.
Standard forms such as the PSSCOC and the SIA conditions set out how and when claims are made, but the statutory right sits underneath the contract. A term that tries to remove or dilute the right to claim does not survive the Act.
GST sits on top
The valuation is a net figure. GST at nine per cent, the rate since the first of January 2024, is added on the tax invoice. Keep the claim and the tax separate in your own records so the amount the SOP Act works on is always the net certified value, not a gross figure with tax buried inside it.
Why discipline here pays
If the respondent serves no payment response, or serves one late, the claimant can proceed to adjudication under the SOP Act and the adjudicator will look first at what was claimed and what, if anything, was validly answered. A clean, dated, itemised payment claim is the foundation of that case. A vague one hands the respondent room to argue.
Value carefully, claim cumulatively, serve properly, and diary the date. The claim you can prove you served on time is the one the Act will help you enforce.
QScope builds each payment claim from the cumulative valuation, carries the tax line, and stamps the service date so the SOP Act timeline runs from a number you can defend.