Assignment of Debt in Singapore: Selling an Unpaid Invoice and Suing as the Assignee

Short answer: A Singapore company can sell an unpaid invoice by assigning the debt. If the assignment is absolute, in writing signed by the seller, and the debtor gets express written notice, section 4(8) of the Civil Law Act 1909 lets the buyer sue alone. Otherwise it is usually an equitable assignment, and the seller generally must be joined.

Assignment of debt in Singapore is how a business turns an unpaid invoice into cash, moves receivables within a group or passes them to the buyer of its business. It is also how a company can be sued by a stranger for an invoice it owes someone else. This guide covers legal and equitable assignments, non-assignment clauses, how the assignee sues, the debtor’s defences, whom to pay after a notice of assignment, and where the Companies Act and the Debt Collection Act 2022 come in.

Raffles Corporate Services works with a panel of experienced Singapore law firms who offer cost-effective and efficient legal service and advice. This article is general information only and is not legal advice.

What is an assignment of debt, and how do legal and equitable assignments differ?

An assignment of debt transfers a creditor’s (the assignor’s) right to be paid to someone else (the assignee). The debtor still owes the same money; only the person entitled to receive it changes. Companies do this to raise cash by selling invoices at a discount (factoring), to restructure a group, on the sale of a business, or to settle a debt of their own.

A legal (statutory) assignment meets every requirement of section 4(8) of the Civil Law Act 1909 and lets the assignee sue alone. One that falls short, for example because notice was never sent or only part of the debt was transferred, may still work in equity.

In Lanxess Pte Ltd v APP Chemicals International (Mau) Ltd [2009] SGHC 25 (unreported), the High Court held that the notice must be clear, unambiguous and unconditional, but needs no prescribed form; signed statements of account issued by the assignee were enough on the facts. The court also confirmed that an equitable assignment needs no notice to the debtor.

Which laws govern the assignment and a claim by the assignee?

Section 4(8) of the Civil Law Act 1909 is the core rule. The Rules of Court 2021 govern the court action, the Companies Act 1967 applies if the assignment is security, and the Debt Collection Act 2022 applies if the assignee collects acquired debts as a business.

The Ministry of Finance describes stamp duty as a tax on dutiable documents relating to immovable property in Singapore and to stocks or shares. An assignment of an ordinary trade debt is neither, but check with IRAS or your solicitor if the assigned rights are tied to property or shares.

Can a contract stop the debt from being assigned?

Yes. Many contracts say neither party may assign without the other’s prior written consent. In DGJ v Ocean Tankers (Pte) Ltd (in liquidation) [2024] SGCA 57 (unreported), the Court of Appeal agreed that the obligor was entitled to ignore an assignment made in breach of such a clause and treat the claim as still lying with the assignor, leaving open whether the assignment might still bind the assignor and assignee between themselves. A buyer of an invoice should read the contract first and, if there is a restriction, get the debtor’s written consent before paying.

Who can sue on an assigned debt, and when must the assignor be joined?

A legal assignee sues in its own name. An equitable assignee generally must join the assignor as a party, so the debtor is not exposed to being sued twice for the same debt.

That joinder rule is procedural. In Asidokona Mining Resources Pte Ltd v Alternative Advisors Investments Pte Ltd [2023] SGHC(A) 6 (unreported), the Appellate Division upheld the trial judge’s decision to dispense with the requirement that the equitable assignor remain a party, finding the risk of double recovery overstated. The appeal still succeeded on other grounds, concerning ratification of the underlying documents, which is a reminder that every link in the chain of authority must be sound. Under Order 9, Rule 10 of the Rules of Court 2021, the court may add or remove parties.

• Security for costs. Under Order 9, Rule 12, a defendant may seek security against a nominal claimant suing for someone else’s benefit, or against a non-party who assigned its right in the action for a share of the recovery.
• Time. The assignee steps into the assignor’s shoes; assignment does not give the debt a new limitation period. Check the dates against our guide to the debt limitation period in Singapore before buying an old invoice.

How does an assignee recover the debt, step by step?

The assignee makes sure the assignment is effective, gives notice, demands payment and, if the debtor still refuses, sues. Court proceedings are conducted by a Singapore Advocate and Solicitor.

1. Review the contract for a non-assignment clause, governing law and any arbitration clause.
2. Pass board resolutions approving the sale and purchase. Under section 157A of the Companies Act 1967, the business of a company is managed by or under the direction of its directors.
3. Sign a written assignment of the whole debt, identifying the invoices, debtor and price, signed by the assignor.
4. Give the debtor express written notice stating the debt assigned, the assignee’s name and that payment must now go to the assignee. Keep proof of delivery.
5. Send a letter of demand containing an offer of amicable resolution open for at least 14 days (Order 5).
6. If unpaid, the law firm files an originating claim in the assignee’s name, pleading the assignment and notice, and joins the assignor if the assignment may only be equitable.
7. A debtor served in Singapore must file a notice of intention to contest within 14 days, and a defence within 21 days, after the statement of claim is served (Order 6, Rules 6 and 7). If it does neither, the assignee can apply for judgment.

What defences does the debtor keep, and whom should it pay after a notice of assignment?

Broadly, all of them. Section 4(8) passes the debt “subject to all equities”, so the assignee takes it with the same weaknesses the assignor had.

• Disputes about the debt itself: defective work, short delivery, a wrong price, or payment already made to the assignor before notice.
• Set-off against the assignor. Closely connected cross-claims, such as damages for defects under the same contract, are the most likely to survive; for unrelated cross-claims, the timing of the notice usually matters. See our guide to counterclaim and set-off in Singapore.
• An invalid assignment: no signed writing, a defective notice, part of the debt only, or a non-assignment clause.
• Limitation, where more than 6 years have passed without a signed acknowledgment or part payment.

Your company has received a notice of assignment: what now?

The notice tells the debtor whom to pay. Once a valid section 4(8) notice arrives, the assignee can give a good discharge, and paying the original creditor afterwards risks paying twice. Before paying anyone:

1. Check the notice is written, unconditional and identifies the debt and the assignee. If it comes only from the alleged assignee, ask for a copy of the signed assignment or written confirmation from your supplier.
2. Check your contract for a non-assignment clause and decide, with advice, whether to consent or rely on it.
3. Verify new bank details by phone with a known contact at your supplier; a fake notice changing the payee is a known fraud tactic (see our guide to invoice fraud and changed bank details).
4. Tell both parties in writing of any dispute, credit or set-off you claim.
5. If both the assignor and assignee demand payment and you cannot tell who is right, a solicitor can apply for interpleader relief.

When must an assignment of receivables be registered, and does the assignee need a licence?

Registration is needed when the assignment is security rather than a sale. Section 4 of the Companies Act 1967 defines a “charge” to include a mortgage and any agreement to give one, and section 131(3)(f) makes a charge on the company’s book debts registrable.

Particulars must be lodged within 30 days after creation; otherwise the security is void against the liquidator and any creditor, though the loan stays repayable (section 131(1) and (2)). ACRA’s charge registration guidance gives 37 days for charges created outside Singapore. The company must also keep a copy of the instrument and a register of charges at its registered office (section 138). A security assignment is not a legal assignment under section 4(8), which excludes assignments “by way of charge only”. Our guide to registering a charge in Singapore covers the Bizfile steps. Whether a factoring agreement is a sale or a security depends on its terms, so ask your solicitor.

On licensing, the Debt Collection Act 2022 defines a “debt collection business” to include collecting a debt the collector has acquired, and section 6(1) bars carrying it on without a licence. A first offence carries a fine of up to S$20,000, up to 2 years’ imprisonment, or both (section 6(5)). Excluded persons include Singapore law practices and a person who acquires debts by buying or merging with a business, other than a debt collection business, together with its receivables. A company taking a one-off assignment from a trading partner should ask its solicitor whether it is carrying on a business at all. See our Debt Collection Act 2022 guide.

What documents are needed, and what are the timeline and costs?

The assignee must prove three things: the original debt, the assignment and the notice. Solicitors’ fees are the main cost if the debtor does not pay on notice.

Assumptions: Singapore parties, Singapore law, no arbitration clause, service in Singapore.

What does the company secretary prepare, and what does the solicitor do?

The company secretary handles corporate approvals, registers and ACRA filings. The Singapore Advocate and Solicitor advises on the assignment, drafts the deed and notice, and conducts any proceedings.

Raffles Corporate Services does not give legal advice or act in court; a law firm from our panel handles proceedings. If you are about to buy, sell or pay a disputed invoice, speak to a lawyer first.

Common mistakes

• Never giving the debtor written notice, so the assignor must later be found and joined.
• Assigning part of an invoice and expecting to sue alone.
• Buying a debt without reading the contract’s non-assignment clause.
• Sending a conditional or vague notice.
• Treating a security assignment as a sale and missing the 30-day ACRA deadline.
• For debtors: paying a new payee on an unverified email, or paying the old creditor after valid notice.

Frequently asked questions

Can I sell an unpaid invoice to another company in Singapore?

Generally yes, unless your contract with the customer prohibits assignment. Use a signed written assignment of the whole debt and give the customer express written notice so the buyer can sue in its own name.

Does the debtor have to agree to the assignment?

Section 4(8) requires notice to the debtor, not consent. Consent matters in practice where the contract contains a non-assignment clause.

Can the assignee recover more than the assignor could?

No. The assignee takes the debt subject to the equities, and the debtor keeps its defences, including relevant set-offs.

Do we need to tell ACRA when we sell our receivables?

Not for an outright sale. If receivables are assigned as security for a loan, the charge on book debts must be registered within 30 days under section 131 of the Companies Act 1967.

Last reviewed: 4 November 2026. The Editorial Team, Raffles Corporate Services.