Statute Details
- Title: Weights and Measures Act 1975
- Act Code: WMA1975
- Type: Act of Parliament
- Status / Version: Current version as at 27 Mar 2026
- Commencement: (Original Act commenced 1 January 1976; current consolidated version reflects later amendments)
- Legislative Purpose (long title): To provide for the use of uniform weights and measures throughout Singapore
- Key Parts: Part 1 (Preliminary); Part 2 (Units and Standards); Part 3 (Weighing and Measuring for Trade); Part 4 (Regulation of Certain Transactions in Goods); Part 5 (Administration); Part 6 (Miscellaneous)
- Key Sections (from extract): ss 1–41; including ss 5–15 (trade instruments and offences), ss 16–28A (regulated transactions), and ss 29–31A (administration and recall)
- Schedules: First Schedule (metric unit definitions); Second Schedule (metric measures and weights); Third Schedule (customary weights)
- Related Legislation (as provided): Competition Act 2004; Measures Act 1975; Security Act 2025
What Is This Legislation About?
The Weights and Measures Act 1975 (“WMA”) is Singapore’s core statute governing the accuracy, legality, and use of weights and measures in commercial life. In practical terms, it is designed to ensure that when goods are sold, measured, weighed, or otherwise quantified for consumers and businesses, the quantities are reliable and expressed using lawful units and standards.
The Act addresses two broad areas. First, it regulates the measurement system itself: the units of measurement that may be used, the standards that define them, and the instruments used for weighing and measuring in trade. Second, it regulates how trade transactions are conducted—for example, how certain goods must be sold, what constitutes “short weight,” and what safeguards and defences may be available to traders.
Although the Act is technical in subject matter, its legal effect is straightforward: it creates compliance duties for traders and instrument users, empowers enforcement officers to inspect and test, and provides offences and penalties to deter under-measurement and misleading quantity practices.
What Are the Key Provisions?
1) Units and standards of measurement (Part 2: ss 3–4)
Part 2 establishes the legal framework for measurement units. Section 3 provides for the units of measurement that may be used, while section 4 provides for standard weights and measures. The First and Second Schedules supply the metric definitions and the metric system measures and weights, reinforcing that Singapore’s lawful measurement regime is anchored in the metric system.
2) “Use for trade” and lawful measurement instruments (Part 3: ss 5–15)
Part 3 is the heart of the Act for practitioners dealing with compliance and enforcement. Section 5 defines the meaning of “use for trade,” which is crucial because many obligations and offences apply only when weighing or measuring is carried out in a trade context (e.g., selling goods, charging by quantity, or otherwise using measurement to determine commercial value).
Section 6 sets out units of measurement and weights lawful for use for trade. This is where the Act links measurement accuracy to legal form: even if an instrument is accurate, using an unlawful unit or weight system may still create liability.
Sections 7, 7A, 7B, 8, and 9 regulate weighing or measuring instruments used for trade. The Act distinguishes between inspection/testing by an Authorised Verifier (ss 7A and 29A) and inspection/testing by an inspector (s 7B). It also provides for approved patterns of instruments (s 8) and general specifications (s 9). In other words, instruments are not merely “any scales”: they must conform to approved designs and specifications, and they must be capable of passing inspection and testing.
Section 11 addresses offences connected with affixing of stamps and Accuracy Labels. This is a common enforcement pathway: if a trader uses an instrument without proper certification markings, or tampers with them, the Act treats that as an offence. Section 12 gives the authorities power to ban the use of a weighing or measuring instrument, reflecting the Act’s protective purpose.
Section 14 and 15 deal with other offences connected with instruments and evidence of possession of instruments for use for trade. For lawyers, these provisions matter because they can affect how cases are pleaded and proved: possession and use are often central factual issues in measurement-related prosecutions.
3) Regulating transactions in particular goods (Part 4: ss 16–28A)
Part 4 moves from instrument regulation to transaction-level regulation. Section 16 provides for transactions in particular goods, and section 17 creates offences in such transactions. While the extract does not list the specific goods, the structure indicates that the Act targets categories of goods where quantity measurement is especially important (for example, where consumers are vulnerable to short weight or where measurement practices are prone to abuse).
Section 18 addresses sale of goods in metric units, reinforcing that lawful units are not optional. Section 19 addresses short weight (and related issues). This is one of the most practically significant provisions for disputes involving under-delivery: it provides the statutory basis for alleging that a trader supplied less than the quantity represented or required.
Sections 20 and 21 introduce a compliance-oriented approach by allowing certain warranty-related and other defences and safeguards for traders. Section 21A creates an offence relating to a document containing particular statements, which is relevant where quantity is communicated through invoices, labels, or other documents.
Sections 22 and 23 address offences due to default of third persons and offences originating in countries outside Singapore. These provisions are important for cross-border supply chains and outsourcing arrangements: they can affect whether a trader can be held liable for measurement-related misconduct by upstream parties, and how liability is framed.
Sections 24 and 25 provide special powers of inspectors with respect to certain goods and documents. Section 26 introduces check-weighing of certain road vehicles, and section 27 provides for test purchases. These enforcement tools are designed to detect non-compliance in real commercial settings.
Sections 28 and 28A regulate selling by quantity and related practices. Section 28 covers selling by quantity, making quantity known, and weighing in presence—concepts that protect transparency and prevent “surprise” measurement outcomes. Section 28A addresses selling by retail by weight, measure or number, which is particularly relevant to consumer-facing businesses.
4) Administration, inspection powers, and recall (Part 5: ss 29–31A)
Part 5 establishes how the Act is administered. Section 29 provides for administration of the Act and section 29A allows the appointment of Authorised Verifiers. These appointments are central to the testing regime for instruments.
Section 30 provides general powers of inspection and entry. Section 31 provides powers of arrest, etc. (as indicated by the heading). Section 31A is especially noteworthy: it gives power to require the recall of weighing or measuring instrument supplied. This is a strong consumer-protection mechanism and can be operationally significant for manufacturers, importers, and suppliers of instruments—particularly where an instrument is later found to be non-compliant or unsafe for trade use.
5) Miscellaneous: offences, penalties, jurisdiction, and corporate liability (Part 6: ss 32–41)
Part 6 includes obstruction offences (s 32), composition of offences (s 33), jurisdiction (s 34), penalties (s 35), and offences by corporations (s 36). Section 36A refers to fees collected by the Commission, and section 36B provides for exemption. Sections 37–38 cover regulations and orders, while sections 39–41 address application to the Government, saving, and transitional provisions.
For practitioners, the corporate liability provision is often critical. Where a business entity is prosecuted, section 36 typically determines how liability is attributed to corporations and how compliance failures are handled in corporate settings.
How Is This Legislation Structured?
The WMA is organised into six parts. Part 1 sets out preliminary matters: short title and interpretation (including key defined terms such as “Authorised Verifier,” “Accuracy Label,” and “catch weight goods”). Part 2 establishes lawful units and standards. Part 3 regulates weighing and measuring instruments used for trade, including inspection/testing, approved patterns, specifications, and instrument-related offences. Part 4 regulates certain transactions in goods, including sale practices, short weight, and defences/safeguards. Part 5 provides the administrative and enforcement machinery: appointment of verifiers, inspection powers, arrest powers, and recall powers. Part 6 contains miscellaneous provisions on obstruction, composition, jurisdiction, penalties, corporate offences, exemptions, and regulation-making.
The Act also includes three schedules: metric unit definitions (First Schedule), metric measures and weights (Second Schedule), and customary weights (Third Schedule). These schedules support the statutory definitions and provide the technical backbone for lawful measurement.
Who Does This Legislation Apply To?
The WMA applies broadly to persons and businesses that use weighing or measuring instruments for trade and to those who engage in regulated transactions in goods. This includes retailers, wholesalers, manufacturers, importers, and service providers whose commercial activities involve measuring, weighing, or quantifying goods for sale or commercial exchange.
It also applies to persons involved in the supply chain of measurement instruments—particularly where instruments are supplied for use in trade. The recall power under section 31A indicates that manufacturers and suppliers may face obligations or consequences if instruments are found non-compliant. Enforcement is carried out by inspectors and authorised verifiers appointed under the Act, with the Competition and Consumer Commission of Singapore referenced in the interpretation of “Commission” (linking the Act to consumer protection and competition-related institutional oversight).
Why Is This Legislation Important?
The WMA is important because it underpins trust in commercial quantity claims. In many consumer and business disputes, the central question is not only whether goods were delivered, but whether the quantity was measured and sold correctly. By setting lawful units, standards, and instrument requirements, the Act provides a legal baseline for determining whether a trader’s quantity practices were compliant.
From an enforcement perspective, the Act equips inspectors with practical tools: inspection and entry powers, testing and verification regimes, check-weighing of vehicles, and test purchases. These mechanisms allow authorities to detect non-compliance in both fixed premises and operational logistics contexts.
From a compliance and risk-management perspective, the Act’s offence structure and evidential provisions (including possession-related evidence and instrument marking offences) mean that businesses should treat measurement compliance as an ongoing operational requirement. Businesses should ensure that instruments used for trade are properly approved, tested, and labelled, and that sales practices (including retail weighing and quantity disclosure) align with statutory requirements and any applicable regulations.
Related Legislation
- Competition Act 2004
- Measures Act 1975
- Security Act 2025
Source Documents
This article provides an overview of the Weights and Measures Act 1975 for legal research and educational purposes. It does not constitute legal advice. Readers should consult the official text for authoritative provisions.