What Is a Coalition Government? How Parties Share Power

A coalition government is a government formed by two or more political parties that agree to govern together. It usually happens when no single party has won a majority of seats in parliament, so no party can pass laws or survive a vote of confidence on its own.

In some countries coalitions are the normal way of governing. In others, such as the United Kingdom, they are rare enough to be big news. Both experiences say something about how parliaments work.

Why coalitions form

In a parliamentary system, the government needs the support, or at least the tolerance, of a majority of members of parliament. If one party holds more than half the seats, it can govern alone. If nobody does, the result is often called a hung parliament, and parties have to work out who can command a majority.

How often that happens depends largely on the electoral system. First past the post tends to give one party a majority even on a minority of the vote, so coalitions are unusual. Proportional systems give seats in line with votes, and because few parties win more than half the vote, coalitions are common.

How a coalition is put together

There is no single procedure, but most coalitions go through the same steps.

1. Talks. After the result, party leaders and negotiating teams meet to see whether their policies can be reconciled. Talks can last days, as in the UK in 2010, or months, as has happened in several European countries.
2. A coalition agreement. The parties write down what the government will do, which promises each side gives up and how disagreements will be handled. Some agreements run to dozens of pages.
3. Sharing out posts. The parties agree who becomes head of government and how ministries are divided, often in rough proportion to each party's seats.
4. Approval. Depending on the country, the head of state appoints the government, parliament votes to confirm it, or both. Some parties also ask their own members to approve the deal.

Once in office, ministers from all coalition parties are normally bound by collective responsibility: they defend the government's decisions in public, even ones their own party opposed in private.

Examples

United Kingdom, 2010–2015

The general election of May 2010 produced the first hung parliament at Westminster since February 1974. The Conservatives won 306 seats, short of the 326 needed for a majority. After five days of talks they formed a coalition with the Liberal Democrats, who had 57 seats. It was the first full coalition in the UK since the Second World War, and it lasted the whole five-year parliament.

Germany

German governments are almost always coalitions. In November 2024 the three-party "traffic light" coalition of the SPD, the Greens and the FDP collapsed, which led to an early election on 23 February 2025. After that election the CDU/CSU and the SPD formed a new coalition government.

South Africa, 2024

In the general election of May 2024 the African National Congress won 40.18% of the vote and lost the parliamentary majority it had held since 1994. On 14 June 2024 the ANC, the Democratic Alliance, the Inkatha Freedom Party and the Patriotic Alliance announced a Government of National Unity. Six more parties then joined, making a grand coalition of ten parties with 287 of the 400 seats in the National Assembly.

Types of coalition and arrangements short of one

Not every deal between parties is a full coalition. The main variations are:

Arrangement	What it means
Majority coalition	The governing parties together hold more than half the seats.
Minority coalition	Several parties govern together but still lack a majority, and rely on others case by case.
Grand coalition	The largest parties, often normal rivals, govern together.
Confidence and supply	A party stays outside government but promises to back it on confidence votes and the budget, usually in return for policy or funding commitments.
Minority government	One party governs alone without a majority and wins votes one by one.

A well-known confidence and supply deal followed the UK election of 2017, when the Conservatives lost their majority. The Democratic Unionist Party agreed to support the government on key votes, and the agreement included an extra £1 billion of funding for Northern Ireland.

Coalitions, alliances and electoral pacts

The words are often mixed up, but they describe different things.

• A coalition is usually formed after an election, to govern.
• An electoral pact is agreed before an election: parties agree not to stand against each other in some seats so their supporters are not split. In the 2019 UK election, the Liberal Democrats, the Green Party of England and Wales and Plaid Cymru agreed under the "Unite to Remain" banner that only one of them would stand in 60 constituencies.
• An alliance is a looser term for parties that campaign together, sometimes under a shared name or on a joint list, while keeping their own organisations. Some alliances later merge into a single party; others break up.

Strengths and weaknesses

Supporters of coalition government say it:

• rests on parties that together usually represent a majority of voters;
• forces compromise and tends to moderate extreme proposals;
• brings a wider range of views into government.

Critics say that:

• voters cannot know in advance which promises will survive negotiations;
• small parties can win influence out of proportion to their size by being needed for a majority;
• forming and holding together a coalition can be slow, and coalitions can collapse mid-term.

Whether these are costs worth paying is one of the oldest arguments about democratic design.