Parliament and elections: statistics terms explained

How laws are made, how MPs vote and how elections are won: the parliamentary and electoral terms behind claims about votes, majorities and party funding.

First past the post

The voting system used for UK general elections: each constituency elects one MP, and the candidate with the most votes wins, even without a majority.

First past the post is the voting system used to elect MPs to the House of Commons. The UK is divided into 650 constituencies; in each, voters mark one candidate, and whoever gets the most votes wins the seat, whether or not they have more than half. It is also used for most local council elections in England and Wales and, following the Elections Act 2022, for mayoral elections in England and police and crime commissioner elections.

Why it matters when checking a claim

Seats and votes differ. A party's share of seats can be much larger or smaller than its share of votes. Claims about a "mandate" or a "landslide" should give both figures.
Other UK elections use other systems. The Scottish Parliament and Senedd use proportional systems, and Northern Ireland Assembly and Scottish council elections use the single transferable vote.

See how Scottish Parliament elections work, the Senedd voting system and where to find election results.

Also searched as: FPTP, first past the post meaning, simple plurality, UK voting system

Official definitions: UK Parliament: Voting systems in the UK · UK Parliament: Election results

Short money

Public funding paid to opposition parties in the House of Commons to help them carry out their parliamentary work.

Short money is annual public funding for opposition parties in the House of Commons, to help them carry out parliamentary business. It is named after Edward Short, the Leader of the House who introduced it in 1975. A party qualifies if it won at least two seats at the last general election, or one seat and more than 150,000 votes. It has three parts: general funding based on seats and votes won, travel expenses, and funding for the Leader of the Opposition's office. The equivalent in the House of Lords is called Cranborne money.

Why it matters when checking a claim

Not a campaign fund. Short money is for parliamentary work, not election campaigning. Party donations and campaign spending are regulated separately by the Electoral Commission.
Amounts are published. The House of Commons publishes the allocations to each party, and the House of Commons Library briefing explains the rules.

See how to find party donations.

Also searched as: Short money meaning, opposition party funding, Cranborne money, Short money parliament

Official definitions: House of Commons Library: Short Money

Statutory instrument

A type of secondary legislation made by ministers using powers in an Act of Parliament, often used to set detailed rules, rates or start dates.

A statutory instrument (SI) is the most common form of secondary (delegated) legislation. An Act of Parliament (the "parent Act") gives ministers power to make more detailed law later, such as setting benefit rates, changing regulations or bringing parts of an Act into force. Several thousand SIs are made in some years.

How Parliament scrutinises them

Negative procedure: the SI becomes law unless either House objects within a set period. Most SIs follow this route.
Affirmative procedure: both Houses (or the Commons alone for some financial matters) must actively approve it.

Why it matters when checking a claim

A claim that a rule "was never voted on" may be accurate for a negative SI; the legislation itself will show which procedure applied.
Every SI is published with an explanatory memorandum on legislation.gov.uk, with its number and commencement date.

See how to check if a law is in force.

Also searched as: SI, secondary legislation, delegated legislation, statutory instrument meaning, regulations

Official definitions: legislation.gov.uk: UK Statutory Instruments · UK Parliament: Secondary legislation

Royal Assent

The monarch's formal agreement that turns a bill passed by Parliament into an Act. Parts of the Act may still not be in force until later.

Royal Assent is the final stage in making a bill into law. Once both Houses of Parliament have agreed the text, the monarch gives formal assent and the bill becomes an Act of Parliament. Assent is announced in each House and the Act is published on legislation.gov.uk.

Why it matters when checking a claim

Law is not the same as in force. Many Acts contain commencement provisions, so some or all sections only take effect on a later date or when a minister makes a commencement order. A claim that something "is now law" should be checked against the commencement information.
Bills can fall. A bill that has not received Royal Assent when Parliament is prorogued or dissolved normally falls unless it is carried over.
Devolved Acts. Acts of the Scottish Parliament and Senedd also receive Royal Assent.

See has a bill become law and how to check if a law is in force.

Also searched as: Royal Assent meaning, Act of Parliament, when does a bill become law, commencement

Official definitions: UK Parliament: Royal Assent · legislation.gov.uk: UK Public General Acts

Second reading

The first full debate on the main principles of a bill in the House of Commons or House of Lords, usually ending in a vote if opposed.

The second reading is the stage at which MPs or peers debate the general principles of a bill for the first time. In the House of Commons, a minister or the member in charge opens the debate, and the House may then vote on whether the bill should proceed. Detailed line-by-line scrutiny follows at committee stage and report stage, before third reading.

Why it matters when checking a claim

Voting for a second reading is not voting for the final law. A bill can be heavily amended later. Claims about how an MP "voted for" a measure should say which stage the vote was at.
Private members' bills. Many pass second reading but run out of time before becoming law.
The record is public. Debates are in Hansard, and votes (called divisions) are published.

See how did my MP vote.

Also searched as: second reading of a bill, second reading meaning, stages of a bill, second reading debate

Official definitions: UK Parliament: Second reading (House of Commons) · UK Parliament: Bills before Parliament

Working majority

The number by which a government's MPs outnumber all other MPs who actually vote, after allowing for the Speaker, deputies and MPs who do not take their seats.

A government's majority is the number of seats its party holds over all other parties combined. The working majority adjusts this for MPs who do not normally vote: the Speaker and three Deputy Speakers, and Sinn Féin MPs, who do not take their seats. The working majority is therefore usually a little larger than the simple majority.

Why it matters when checking a claim

Different numbers circulate. "Majority" can mean the lead over the second party, the lead over all others, or the working majority. Check which is used.
It changes during a Parliament. By-elections, defections, suspensions of the whip and deaths alter party totals. The House of Commons publishes the current state of the parties.
Whip status matters. An MP suspended from a party may be listed as independent even if elected for that party.

See how many MPs are there.

Also searched as: government majority, majority in the House of Commons, effective majority, working majority meaning

Official definitions: UK Parliament: State of the parties · UK Parliament: Election results

By-election

An election held to fill a single vacant seat between general elections, for example after an MP resigns, dies or is removed by a recall petition.

A by-election fills a vacancy in one constituency between general elections. A Commons seat can become vacant when an MP dies, resigns (formally by taking a Crown office such as the Chiltern Hundreds), is disqualified, or loses a recall petition under the Recall of MPs Act 2015. By-elections also happen for council seats and, in some cases, devolved legislatures.

Why it matters when checking a claim

Compare with the right baseline. "Biggest swing" or "record result" claims depend on whether the comparison is with the last general election or with notional results on current boundaries.
Turnout is usually lower than at general elections, so vote shares and raw votes can tell different stories. See turnout and swing.
Official results are declared by the local returning officer and published on UK Parliament's election results service.

Also searched as: by-election meaning, by-election uk, recall petition, Chiltern Hundreds

Official definitions: UK Parliament: By-elections · legislation.gov.uk: Recall of MPs Act 2015

Turnout

The share of registered voters who voted in an election. Small differences in how it is calculated can change the figure.

Turnout is the proportion of the electorate who voted. It is normally calculated as the number of votes cast divided by the number of people on the electoral register for that election.

Why it matters when checking a claim

Valid votes or ballot papers? Some figures count only valid votes; others include rejected ballot papers. The Electoral Commission states its definition in its results data.
Registered voters, not adults. Turnout uses the register, not the whole adult population. People who are eligible but not registered are not counted, so turnout as a share of the eligible population is lower.
Compare like with like. General, local, devolved and by-election turnouts differ greatly. Changes to the franchise or voter ID rules can also affect comparisons over time.

See how many people are registered to vote and the Electoral Commission source guide.

Also searched as: voter turnout, turnout uk general election, election turnout meaning

Official definitions: Electoral Commission: Results and turnout at past elections · UK Parliament: Election results

Swing

A measure of how far support has moved between two parties since a previous election, usually the average of one party's gain and the other's loss.

Swing summarises the change in support between two parties from one election to another. The most common version (often called Butler swing) is the average of the change in the two parties' vote shares, in percentage points. If party A rises by 6 points and party B falls by 4 points, the swing from B to A is 5 points.

Why it matters when checking a claim

Between which parties? Swing only describes two parties. With several parties gaining and losing, it can hide important shifts.
Which baseline? After boundary changes, swings are calculated against notional results for the new seats, which are estimates.
Points, not per cent. A swing of 10 points is not a 10% change in support.

UK Parliament's election results service publishes vote shares and changes for each constituency.

Also searched as: electoral swing, Butler swing, swing meaning election, two-party swing

Official definitions: UK Parliament: Election results · Electoral Commission: Results and turnout at past elections

Division (vote in Parliament)

A formal recorded vote in the House of Commons or House of Lords, in which members' names are listed by how they voted.

A division is a formal vote in either House of Parliament. In the House of Commons, MPs vote Aye or No and are counted by tellers; their names are recorded and published. Many questions are decided without a division, by voice, when nobody objects.

Why it matters when checking a claim

There is no formal abstention. MPs who do not vote may be abstaining, absent for other reasons, or "paired" with an MP from the other side. A missing vote does not show which.
Know what the vote was on. A vote may be on an amendment, a procedural motion or a stage of a bill, not the bill itself. See second reading.
The official record. Division lists are published on the Parliament votes website and in Hansard. See how to check a quote in Hansard.

See how did my MP vote.

Also searched as: Commons vote, division list, how MPs vote, division lobby, division bell

Official definitions: UK Parliament: Divisions · UK Parliament: Votes in Parliament