The clearest case is an undisputed invoice that has aged past its payment terms, where reminders have gone unanswered and the debtor is a company you suspect can pay but will not. Here the statutory demand is the sharpest tool available, because the mere prospect of a winding-up application, which becomes a matter of public advertisement, tends to concentrate a director's mind faster than any letter. A supplier owed more than S$15,000 on clean paperwork is the textbook user.
An ordinary letter of demand, without the statutory escalation, suits smaller sums, ongoing commercial relationships you would rather preserve, and debts you may want to send to mediation or the Small Claims Tribunals. It is also the right first move where the amount is close to the threshold and you would prefer not to commit to insolvency proceedings. Landlords chasing arrears sit in a distinct lane: rent recovery has its own dedicated route, and our letter of demand for rent arrears under the Distress Act is drafted for that scenario rather than the general commercial demand.
Two edge cases deserve flagging. First, where the debt is disputed on substantial grounds, serving a statutory demand is dangerous: the debtor can obtain an injunction restraining the winding-up application and pursue you for costs and, in a bad case, damages for abuse of process. Sue in the ordinary courts, obtain judgment, and only then demand. Second, where the claim is for unliquidated damages, the sum is not yet ascertained and cannot found a statutory demand until a court or the parties have fixed it.