Political Parties

The party system is based on political groups with their own policies, which compete for the support of the public to win power. In Parliament, the two parties with the most Members of Parliament (MPs) form the government and the opposition.

About political parties

A political party is an organised group of people who have similar ideas about how the country should be run. Their aim is to get their candidates elected to political power.

After a general election, the party with the most MPs usually forms the new government. The second largest party becomes the official opposition, with its own leader and ‘shadow cabinet’.

Most candidates in elections, and almost all winning candidates, belong to one of the main parties. If an MP doesn’t have a political party, they are known as an ‘Independent’.

History of the party system

The system of political parties has existed since at least the 18th century. It evolved from the historical division of Whigs and Tories in the Stuart period. For the past 150 years, Britain has had a mainly two-party system, in which two parties dominate although there may be other parties.

Since 1945, either the Conservative Party or the Labour Party has held power. The Liberal Democrats, the third biggest party in the UK, were formed when the Liberal Party merged with the Social Democratic Party in 1988.

Political parties represented at Parliament

The UK has a wide range of political parties, including national parties in Scotland, Wales and Northern Ireland. The following parties have members in the House of Commons or the House of Lords:

  • Labour Party
  • Conservative Party
  • Liberal Democrat
  • Scottish National Party (SNP)
  • Plaid Cymru – the Party of Wales
  • Democratic Unionist Party (DUP)
  • Sinn Féin
  • Social Democratic and Labour Party (SDLP)
  • Ulster Unionist Party (UUP)
  • Respect
  • UK Independence Party (UKIP)
  • Independent Labour
  • Independent Conservative

Many more parties compete in elections. You can access the full register of political parties on the Electoral Commission website.

The role of political parties in Parliament

The effectiveness of the party system in Parliament relies on the relationship between the government and the opposition parties.

The opposition parties contribute to policy and legislation through constructive criticism, oppose government proposals that they disagree with, and put forward their own policies to improve their chances of winning the next general election.

Leaders of the government and opposition sit opposite each other on the front benches in the debating chamber of the House of Commons. Their supporters, called the ‘backbenchers’, sit behind them.

There are similar seating arrangements in the House of Lords, but peers who don’t wish to be associated with any political party choose to sit on the ‘crossbenches’.