UK Act of Parliament 1985 United Kingdom

Weights and Measures Act 1985

What this means for your business

25 obligations
24 penalties
2 can imprison
2 guides
Enforced by
Trading Standards
Applies to
United Kingdom
On this page
25 compliance obligations, 2 practical guides
Read full text on legislation.gov.uk

What you must do

25 compliance obligations under this legislation — 2 can result in imprisonment.

Management duties 2

Ensure correct quantity statement on packaged goods

Unlimited fine

If you pack or import products for sale, you must make sure the quantity shown on the packaging is accurate. You need to check the weight or measure before the product leaves your control and keep evidence of those checks. This protects consumers and keeps you compliant with the law.

Trader/Business s.47 Trading Standards when you pack or import goods for sale

Mark containers with required weight and quantity information

If you pack or import goods, you must clearly label each container with the legally required details such as net weight, quantity and any other information required by the Weights and Measures Act. This lets customers and inspectors verify what’s inside the package and avoids a breach of the law.

Trader/Business s.48 Trading Standards when you pack or import goods for sale or supply

Offences and prohibitions 23

Apply stamp without verifier's number

If you are a manufacturer (or any person) who puts a prescribed pre‑test stamp on weighing or measuring equipment, the stamp must show the approved verifier’s number. Putting a stamp on without that number is a criminal offence, and the equipment can be seized. Failure to follow this rule can lead to prosecution.

Any Person s.15A Trading Standards

Be liable for another's weights‑and‑measures offence

2 years imprisonment

If a breach of the Weights and Measures Act by someone else occurs because of something you did or failed to do, you can be charged with the same offence even if you were not the original offender. You may face the same penalties that apply to the person who actually committed the offence.

Any Person s.32 Trading Standards

Breach regulations on marking containers or vending machines

If you do not follow any of the regulations made under this section about how containers, pre‑packed goods or vending machines must be marked – for example the quantity, units of measurement, or packer identification – you commit a criminal offence. A court can impose a fine and, in more serious cases, imprisonment, with the exact penalties set by the judge.

Any Person s.23 Trading Standards

Contravene vehicle‑display regulations

If you break a regulation made under section 23 about how quantity information must be shown on a vehicle carrying solid fuel, you commit an offence. The provision does not set a specific fine or prison term – the penalty will follow the standard limits for the offence.

Any Person Schedule 5 Trading Standards

Fail to comply with a check‑weighing request

If a road vehicle is carrying goods that are being sold by weight to a single buyer, the buyer, seller or an authorised inspector can ask the person in charge of the vehicle to have it check‑weighed. The driver or operator must comply unless they have a reasonable excuse. Failing to do so is a criminal offence.

Any Person s.41 Trading Standards

Fail to comply with net‑quantity labelling rules

If your food business is covered by Article 1(3) of the Food Information (FIC) Regulation and you do not follow the rules on stating the net quantity of food – for example, you omit the mandatory net‑quantity label or breach the specific requirements in Articles 8, 9(1)(e) or Chapter V – you commit a criminal offence. The offence does not apply where a recognised exemption or a pre‑Brexit UK measure covers the point in question. A conviction can result in a fine (potentially unlimited) and, in some cases, imprisonment.

Any Person s.31A Trading Standards

Fail to comply with public weighing equipment duties

If you operate or provide weighing or measuring equipment that the public can use, you must ensure the appointed attendant carries out weighings on demand, does so fairly, provides a written statement and proper records, and keeps those records for at least two years. It is also an offence to give false measurements, commit fraud, refuse to give your name and address when asked, or to destroy or fail to produce the required records. Breaching any of these rules makes you guilty of a criminal offence and can lead to fines and/or imprisonment.

Any Person s.20 Trading Standards

Fail to give written statement of quantity on sale

Unlimited fine

When you sell goods that must be quoted by weight, volume or another measured quantity, the law requires you to give the buyer a written statement of that quantity (or leave it at the delivery site if the buyer is absent). If you do not provide this written statement as required, you and anyone acting on your behalf can be prosecuted.

Any Person s.26 Trading Standards

Fail to provide required imperial conversion information

If your business sells goods using metric units, regulations made under this section may require you to display the equivalent imperial measurement or show conversion tables. Not providing the required information is a criminal offence. Penalties – including fines, possible imprisonment and how the case is tried – are set out in the specific regulations, not in the Act itself.

Any Person s.9 Trading Standards

Give false written warranty for goods

If you sell goods and provide a written warranty that the quantity, pre‑packing or other statement about the goods is false, you commit a criminal offence. The same applies if you deliberately attach a warranty that belongs to different goods. Conviction can lead to a fine and/or imprisonment, with the exact penalties set by the wider Weights and Measures legislation.

Any Person s.33 Trading Standards

Insert or use documents with materially incorrect statements

If you knowingly, or ought to have known, that a required document (such as a label, pack‑statement or specification) contains a statement that is materially incorrect, and you insert that statement, cause it to be inserted, or use the document for the purposes of the Weights and Measures Act while the incorrect statement remains, you commit an offence. A conviction can result in a fine and/or imprisonment, but the exact penalties are set out elsewhere in the Act.

Any Person s.31 Trading Standards

Obstruct a weights and measures inspector

If you deliberately block, hinder or otherwise prevent a weights and measures inspector from carrying out their duties, you commit a criminal offence. A conviction can result in a fine and/or a prison term, depending on how the case is tried.

Any Person s.80 Trading Standards

Operate public weighing/measuring equipment without a certificate

If you run weighing or measuring equipment that the public can use for a charge (for example a public weighing scale or measuring device) and you do not hold a certificate from the chief inspector proving you have the necessary knowledge, you commit an offence. The offence also covers anyone who allows another person to use the equipment in that way without a certificate. Conviction can lead to a fine and/or imprisonment, but the exact maximum penalties are not stated in this excerpt.

Any Person s.18 Trading Standards

Sell goods in the wrong quantity or packaging

Unlimited fine

If you sell, offer or expose for sale any goods that must be pre‑packed, labelled, or sold by a specific quantity, but you do so in a different quantity, packaging, or without the required information, you commit a criminal offence. The offence also covers possessing such goods for sale or delivery when the required specifications are not met. Conviction can lead to unlimited fines and/or imprisonment, depending on how the courts treat the offence.

Any Person s.25 Trading Standards

Sell goods with less quantity than stated

If you (or anyone on your behalf) sell pre‑packed goods, or goods with a written statement of quantity on the pack or accompanying document, and the actual amount inside is less than the amount shown, you commit a criminal offence unless you can prove the shortfall happened after the sale. The offence also covers those who marked the container with the quantity claim. Conviction can lead to a fine and/or imprisonment, and the case can be tried in either magistrates’ or Crown Court.

Any Person s.30 Trading Standards

Sell less weight or quantity than stated

2 years imprisonment

If you sell goods by weight, measurement or number and give the buyer a smaller amount than you said you were selling, or less than the price charged implies, you commit a criminal offence. It covers any business that sells packaged items, loose goods or bread by weight or count. Conviction can attract an unlimited fine and up to two years’ imprisonment.

Any Person s.28 Trading Standards

Tamper with or misuse stamps on trade weighing/measuring equipment

If you mark, alter, forge, remove or otherwise tamper with the stamp, plug or seal on weighing or measuring equipment that is used for trade, or you sell or offer for sale equipment that carries a forged, transferred or defaced stamp, you are committing a criminal offence. On conviction the equipment can be confiscated and you may face a fine and/or imprisonment as set by the court.

Any Person s.16 Trading Standards

Use false weighing equipment or commit fraud with measuring equipment

If you use, or keep for use, weighing or measuring equipment that is false or unjust for any trade activity, you commit a criminal offence. The same applies if you deliberately use such equipment to carry out fraud, or are a party to that fraud. Conviction can lead to the equipment being confiscated and, depending on the court, possible fines or imprisonment.

Any Person s.17 Trading Standards

Use illegally marked capacity measures for trade

If your business uses a capacity measuring device (e.g., a jug or container) that has been marked with divisions or sub‑divisions to indicate smaller quantities, you are breaking the law. The offence applies to any person who does this, and the offending equipment can be seized. Conviction can lead to a fine or imprisonment as set out elsewhere in the legislation.

Any Person s.10 Trading Standards

Use or supply equipment contrary to its approval certificate

Unlimited fine

If you knowingly use, let others use, sell, or give away weighing or measuring equipment that is subject to a condition on its certificate of approval – or whose certificate has expired, been revoked, or been withdrawn – you commit a criminal offence. The equipment can be confiscated and you may face unlimited fines and possibly imprisonment if convicted.

Any Person s.13 Trading Standards

Use or supply non‑conforming weighing/measuring equipment

If you keep using, let others use, or sell weighing or measuring equipment for trade that you know no longer meets the specifications set by regulations, you commit a criminal offence. The equipment can be seized (forfeited) and you may be prosecuted. The same offence arises if you breach any condition attached to a special exemption for that equipment.

Any Person s.14 Trading Standards

Use unapproved unit of measurement for trade

If you sell goods using a unit of measurement that is not listed in the authorised schedules (or you use a restricted unit such as the troy ounce, carat, certain millilitre capacities or the pint outside the allowed exceptions), you are committing an offence. Any illegal measuring device can be seized and you may be prosecuted, with penalties set by the courts.

Any Person s.8 Trading Standards

Use un‑passed or un‑stamped weighing/measuring equipment for trade

If you use weighing or measuring equipment for trade that has not been inspected, approved and stamped (or you use it after it has been re‑installed without a fresh inspection), you commit a criminal offence. The equipment can be seized and forfeited, and you may face prosecution.

Any Person s.11 Trading Standards

Penalties for non-compliance

24 penalties under this legislation. 2 can result in imprisonment. 6 carry an unlimited fine.

Prison risk

Be liable for another's weights‑and‑measures offence

Unlimited fine and/or 2 years imprisonment

Either way s.32 Penalises: Be liable for another's weights‑and‑measures offence
Prison risk

Sell less weight or quantity than stated

Unlimited fine and/or 2 years imprisonment

Either way s.28 Penalises: Sell less weight or quantity than stated
Unlimited fine

Ensure correct quantity statement on packaged goods

Unlimited fine

s.47 Penalises: Ensure correct quantity statement on packaged goods
Unlimited fine

Fail to give written statement of quantity on sale

Unlimited fine

Summary only s.26 Penalises: Fail to give written statement of quantity on …
Unlimited fine

Sell goods in the wrong quantity or packaging

Unlimited fine

Either way s.25 Penalises: Sell goods in the wrong quantity or packaging
Unlimited fine

Use or supply equipment contrary to its approval certificate

Unlimited fine

Summary only s.13 Penalises: Use or supply equipment contrary to its approval …
Fine

Apply stamp without verifier's number

Penalty applies

s.15A Penalises: Apply stamp without verifier's number
Fine

Breach regulations on marking containers or vending machines

Penalty applies

s.23 Penalises: Breach regulations on marking containers or vending machines
Fine

Contravene vehicle‑display regulations

Penalty applies

Schedule 5 Penalises: Contravene vehicle‑display regulations
Fine

Fail to comply with a check‑weighing request

Penalty applies

s.41 Penalises: Fail to comply with a check‑weighing request
Fine

Fail to comply with net‑quantity labelling rules

Penalty applies

s.31A Penalises: Fail to comply with net‑quantity labelling rules
Fine

Fail to comply with public weighing equipment duties

Penalty applies

s.20 Penalises: Fail to comply with public weighing equipment duties
Fine

Fail to provide required imperial conversion information

Penalty applies

s.9 Penalises: Fail to provide required imperial conversion information
Fine

Give false written warranty for goods

Penalty applies

s.33 Penalises: Give false written warranty for goods
Fine

Insert or use documents with materially incorrect statements

Penalty applies

s.31 Penalises: Insert or use documents with materially incorrect statements
Fine

Obstruct a weights and measures inspector

Penalty applies

s.80 Penalises: Obstruct a weights and measures inspector
Fine

Operate public weighing/measuring equipment without a certificate

Penalty applies

s.18 Penalises: Operate public weighing/measuring equipment without a certificate
Fine

Sell goods with less quantity than stated

Penalty applies

s.30 Penalises: Sell goods with less quantity than stated
Fine

Tamper with or misuse stamps on trade weighing/measuring equipment

Penalty applies

s.16 Penalises: Tamper with or misuse stamps on trade weighing/measuring …
Fine

Use false weighing equipment or commit fraud with measuring equipment

Penalty applies

Either way s.17 Penalises: Use false weighing equipment or commit fraud with …
Fine

Use illegally marked capacity measures for trade

Penalty applies

s.10 Penalises: Use illegally marked capacity measures for trade
Fine

Use or supply non‑conforming weighing/measuring equipment

Penalty applies

s.14 Penalises: Use or supply non‑conforming weighing/measuring equipment
Fine

Use unapproved unit of measurement for trade

Penalty applies

Summary only s.8 Penalises: Use unapproved unit of measurement for trade
Fine

Use un‑passed or un‑stamped weighing/measuring equipment for trade

Penalty applies

s.11 Penalises: Use un‑passed or un‑stamped weighing/measuring equipment for trade

Practical guidance

Our guides explain how to comply with the requirements above.

Sections and provisions

118 classified provisions from this legislation.

Duties 6

  • s.3 Department of Trade and Industry secondary, tertiary and coinage standards. such standard
  • s.47 Duty of packers and importers as to quantity. packers and importers as
  • s.48 Duty of packers and importers as to marking of containers. packers and importers as
  • s.58 Duty of Secretary of State to prepare scheme allocating marks. Secretary of State
  • s.78 Fees received by inspectors.
  • s.87 Secretary of State to report to Parliament.

Offences and penalties 32

  • Schedule 5 Solid Fuel
  • s.8 Units of measurement, weights and measures lawful for use for trade.
  • s.9 Dual marking and conversion charts.
  • s.10 Multiples and fractions of measures and units.
  • s.11 Certain equipment to be passed and stamped by inspector.
  • s.13 Offences in connection with approved patterns of equipment.
  • s.14 General specifications of equipment.
  • s.15A Pre-test stamping by certain manufacturers.
  • s.15 Regulations relating to weighing or measuring for trade.
  • s.16 Offences in connection with stamping of equipment.
  • s.17 Offences relating to false or unjust equipment or fraud.
  • s.18 Keepers of public equipment to hold certificate.
  • s.20 Offences in connection with public equipment.
  • s.23 Regulations as to information.
  • s.25 Offences relating to transactions in particular goods.
  • s.26 Quantity to be stated in writing in certain cases.
  • s.28 Short weight, etc.
  • s.30 Quantity less than stated.
  • s.31A Non-compliance with certain requirements of the FIC Regulation
  • s.31 Incorrect statements.
  • ... and 12 more offences and penalties

Powers 28

  • s.1 Units of measurement.
  • s.6 Testing of other standards and equipment.
  • Schedule 8 Powers of Inspectors and Local Weights and MeasuresAuthority Under Part V
  • Schedule 11 Transitional Provisions and Savings
  • s.11A Approval of persons to verify equipment manufactured etc by them.
  • s.12 Approved patterns of equipment.
  • s.19 Provision of public equipment by local authorities.
  • s.22 Orders relating to transactions in particular goods.
  • s.24 Exemption from requirements imposed under sections 21 to 23.
  • s.27 Exemption from requirements of section 26.
  • s.38 Special powers of inspectors with respect to certain goods.
  • s.40 Powers of inspectors with respect to goods carried on road vehicles.
  • s.42 Power to make test purchases.
  • s.45 Making quantity known to a person.
  • s.62 Power to extend or transfer Unit’s functions and to abolish Unit.
  • s.65 Power to modify Part V.
  • s.69 Local weights and measures authorities.
  • s.70 Annual reports by local weights and measures authorities.
  • s.71 Inspection of local weights and measures arrangements.
  • s.72 Appointment of inspectors.
  • ... and 8 more powers

Definitions 10

  • s.2 United Kingdom primary standards and authorised copies of the primary standards.
  • s.4 Local standards.
  • Schedule 6 Miscellaneous Goods other than Foods
  • s.7 Meaning of ā€œuse for tradeā€.
  • s.39 Powers of inspectors with respect to certain documents.
  • s.68 Interpretation of Part V.
  • s.90 Saving for certain rights in City of London.
  • s.94 General interpretation.
  • s.96 Transitional provisions and savings.
  • Schedule 1 Definitions of Units of Measurement

Exemptions 6

  • s.5 Working standards and testing and stamping equipment.
  • s.34 Reasonable precautions and due diligence.
  • s.35 Subsequent deficiency.
  • s.36 Excess due to precautions.
  • Schedule 4 Sand and Other Ballast
  • Schedule 7 Composite Goods and Collections of Articles