Key issues

Write to your MP

Clock face half hour
If you have more time to compose a letter to your MP, UKMA can help you by outlining key facts and issues. A lot of relevant material exists on this website and this page shows basic points you can make and provides links to more detailed information. Just don’t try to say everything in one letter!

Basic advice

Given that MPs have large volumes of correspondence, try to limit to a major message to a single page as ‘essays’ may not get read. If you really need to get a detailed message across, summarise the key point in a covering letter and put the details in an appendix. Be sure to write only to the MP who represents the constituency where you live. Letters to other MPs will be re-directed back to your own MP. If you are not sure of the name of your MP, refer to the list of MPs on the parliamentary web site.

If you write yourself to a Government Minister, you will get a standard reply from a junior civil servant. However, if you can get your MP to write to a Minister, the convention is that he/she will get a reply from the Minister him/herself. Although the letter may have been drafted by the same civil servant, it will at least have passed across the Minister’s desk and will have engaged his/her attention for a few moments and perhaps been registered as an issue.

Decide the main point you want to make and stay focussed on it:

Background Info

  • The metric system is a modern and consistent set of units that are easy for calculation. They use the decimal system and fit together because they are based on the maths and science of the real world.
  • Although the metric system was first implemented in France, its development has been an international one in which both Victorian and present day British scientists have played a significant role.
  • The metric system is not a ‘foreign imposition’ but was first recommended by a House of Commons Select Committee in 1862. The decision for Britain to adopt the metric system in 1965 was made after lobbying by British industry well before Britain joined the European Economic Community, which later developed into the European Union, in 1973. See the timeline for more details.
  • Britain has chosen a disastrous gradual approach to go from imperial to metric and is still only halfway after almost half a century. Commonwealth countries like Australia, New Zealand and South Africa managed to change in 10 years and had few problems. By contrast, Britain successfully introduced decimal currency very rapidly.

Britain’s measurement units are in a mess

Metric is used for many things in Britain:

  • Most of British industry and government use the metric system in their internal operations and in some of their public or official communications.
  • Schools teach mathematics and science primarily in metric.
  • Many British sports (including rugby union, athletics and swimming) use metres and kilometres.
  • Roads and buildings are designed and constructed exclusively in metres.
  • Petrol is sold by the litre.
  • Travellers taking a car to the Continent or Ireland by ferry or through the Channel Tunnel often have to give their vehicle dimensions in metres
  • Ordnance Survey maps use metric scales and grid and give distances and heights in kilometres and metres respectively.
  • Most shops (especially larger stores and supermarkets) give prices per kilogram or litre.
  • All British meteorological measurement, whether temperature, rainfall or visibility, use metric units.
  • DIY and garden supplies are generally sold in metric quantities.
  • Medical records are kept using metric units, dosages of drugs are determined by body mass in kilograms and babies are weighed in grams.

Yet, much of British everyday life is untouched by metric and indeed in many cases people are forced to use imperial.

  • Distance signs and speed limits are exclusively in miles, yards and miles per hour, whilst feet and inches predominate in height and width restrictions.
  • Advertised petrol consumption is frequently given in miles per gallon
  • Much of the non-specialist media give primarily imperial units (rarely with metric equivalents). Estate agents give floorspace in square feet and room and garden dimensions in feet and inches.
  • Many market traders and some small shopkeepers display weights in pounds and ounces – sometimes (in defiance of the law) without their metric equivalent.
  • Many supermarkets advertise exclusively in imperial even though goods must be priced and weighed in metric at the checkout.
  • Holiday brochures often give summer temperatures in degrees Fahrenheit.
  • Descriptions of criminals wanted by the police are given by the media exclusively in imperial units.

Despite working in metric units, medical professionals feel obliged to convert to imperial when communicating with patients.

Say why Britain should complete metrication

Key reasons to complete the adoption of the metric system include:

Consumer Protection

  • It is very hard to compare prices of food on the High Street because some retailers use metric and others imperial.
  • Consumers are confused by adverts in supermarkets giving prices in imperial when they are charged in metric at the checkout. It is hard to check if the consumer is charged correctly.

Loose bananas
Loose bananas

  • Supermarkets sometimes price the same fruit in up to 3 different ways (by unit weight, per fruit and per bag). Price comparison is impossible.
  • Domestic appliances are often advertised showing ‘gross volume’ in cubic feet. The statutory Energy Label requires the specification of ‘food volume’ in litres. The usable food volume is what is important to the customer.

The information for the same appliance is inconsistent and confusing. The retailer’s label shows “storage capacity” 9.4 cubic feet = 266 litres. The statutory energy label shows a food volume of 228 litres. Where did the extra 38 L come from?

Retailers fridge data label

Statutary energy label

  • TVs and computer monitors are usually advertised showing ‘screen size’ measured in inches. The viewable screen size is usually given in centimetres. The viewable size is what the buyer needs to know.
  • Compulsory use of metric measurements for goods ‘sold from bulk’ was introduced in 2000 without the government providing practical information to help the public changeover.
  • Britain’s weights and measures regulations need to be overhauled to help complete the transition to metric and to better protect the consumer.
  • The government should run a public information campaign to help the public to use metric.
  • The government should seek to phase out imperial units to help ensure a clean changeover.

Road Transport

  • Britain’s road signs are in a mess! Feet and inches for height and width restrictions, yards and miles for distance signs. But visibility in metres.
  • With fuel sold in litres and road distances marked in miles, measuring fuel consumption in either litres/100 km or miles per gallon is awkward.
  • While much of Britain uses the metric system to a great degree, metric units are forbidden on most traffic signs.
  • Although the UK has a derogation (opt-out) from European regulations on using metric road signage, the UK was required to set a date for the changeover until the requirement was removed in 2009. Thus the UK had agreed to change to metric signage in principle.
  • The government has expressed concerns about road sign ‘clutter’ yet it is hard to imagine a sign more cluttered than a British dual unit sign! Metric only signs would be less cluttered than imperial or dual ones.

Cluttered sign
Metric height restriction sign

Metric signs are clearer and simpler than imperial only or dual unit signs.

  • Millions of British motorists drive on holiday abroad each year on metric-signed roads. Holiday makers from Europe – vital for our tourism – are forced to follow UK imperial speed limits with metric speedometers.
  • The huge number of commercial drivers transporting goods between Britain and the rest of Europe must switch between metric and imperial during their journeys.
  • HM Treasury has a National Changeover Plan for the Euro – even though the UK has not agreed to adopt the Euro. Yet the UK has agreed in principle to adopt metric road signage – but there is no National Changeover Plan!
  • With the Republic of Ireland completing the conversion of their roads to metric, Britain will be in complete isolation in Europe with imperial signage and speed limits.
  • Kilometre per hour speed limits allow finer tuning of traffic speeds than miles per hour. This is beneficial for road safety in urban areas and on motorways.
  • The Government should set a target date to complete the changeover to metric road signage.
  • The Government should develop a National Changeover Plan to allow issues to be properly discussed with stakeholders.
  • A public education campaign should be run to prepare the public for driving with metric.


  • It is generally agreed that Britain’s schools went metric by 1974 – earlier in some cases.
  • Using decimal numbers is the foundation of a child becoming numerate.
  • Britain’s currency is decimal, metric units are decimal but imperial units use a hodgepodge of different and largely incompatible number systems.
  • The use of imperial units in the media, on road signs and in the home undermines what children are taught in school. Indeed children grow up with a split between the world of numeracy and the world of conversation.
  • We are creating a generation of mathematically confused children.
  • For the sake of the next generation, Britain should complete its metric conversion to ensure that numeracy skills can be applied to everyday life.