What Happens in the First 100 Days of a New UK Government: A Beginner's Guide
A new government takes office with a moving van's worth of promises and roughly ten weeks before the political weather sets in. The "first 100 days" is an American import — Franklin Roosevelt's opening sprint in 1933 — and it carries no legal force here. Nothing in British law changes on day 100. Even so, the phrase has become Westminster's favourite yardstick for judging a new administration, and it is a genuinely useful window: it is when a prime minister has the most political capital and the least track record.
The 100 days: a yardstick, not a deadline
Incoming ministers inherit a spending plan, a civil service, a legal framework and a diary full of commitments. Some things move within hours: appointments, a first speech, a call to a foreign leader. Others take years: treaties, big infrastructure, anything requiring primary legislation.
So when a headline asks whether a government has "delivered", the honest answer is often "partly, and not yet". Treat the hundred-day mark as a health check rather than a verdict.
A hundred days is a news cycle. A parliament is five years.
The first week: who gets the keys
After the result is clear, the winning party's leader travels to Buckingham Palace, where the monarch asks them to form a government. The Cabinet is named within hours; junior ministers follow over the next day or two. Special advisers — political appointees known as SpAds — arrive alongside career civil servants, who are politically neutral and serve whoever holds office.
Two lists matter more than any speech. The first is who holds the great offices of state: the Treasury, the Home Office, the Foreign Office. The second is who has the prime minister's ear on the subjects they care about. A new department, a merged ministry or an unexpected adviser tells you where attention will go.
Ministers must follow the Ministerial Code and declare their interests; the register is published. If you deal with a government department — a licence, a grant, a contract — expect a short burst of churn while priorities are re-set. Existing deadlines usually still stand.
The King's Speech: the government's shopping list
State Opening of Parliament is the government's to-do list, written by ministers and read aloud by the monarch. It sets out the bills planned for the coming session. Before it begins, the Commons formally debates the Outlawries Bill and the Lords a similar measure — a small ritual signalling Parliament's independence from the Crown.
Several days of debate on the "Humble Address" follow, ending in a vote that a government with a working majority wins comfortably. The speech itself is short; the briefing notes published alongside it are long and far more revealing. Read those. What is left out is often as telling as what is included.
If a government takes over mid-session it may not get a speech immediately, but a new session normally follows before long.
Money: Budgets, forecasts and spending reviews
The Budget is the Chancellor's big set-piece: tax and spending decisions, with forecasts from the Office for Budget Responsibility published the same day. A Finance Bill then turns the tax measures into law. A Spending Review sets departmental budgets, often for several years at a time.
New governments like to say the books are worse than expected. Sometimes they are. Treat the claim as an argument to be tested, not a fact: the numbers come from the Treasury, the OBR and independent analysts such as the Institute for Fiscal Studies.
Remember that announcements are not laws, and laws are not the same as effects. A tax change announced in the spring may not bite until the following April. If a change touches your own tax, pension or benefits, take advice from an accountant or adviser rather than acting on a headline.
From bill to law — and the deadlines that bite
- First reading: a formality. The bill is introduced.
- Second reading: the main debate on the principle of the bill.
- Committee stage: line-by-line scrutiny, usually by a public bill committee of MPs.
- Report stage: the whole House can propose changes.
- Third reading: the final Commons vote.
- The other House: the Lords repeats the process, with "ping-pong" if the two chambers disagree.
- Royal Assent: the monarch signs; the bill becomes an Act.
Few bills run smoothly. Governments usually timetable Commons stages with programme motions, which limits how long each part is debated. The Lords can amend but, under the Salisbury Convention, does not normally vote down at second reading a bill delivering a manifesto commitment.
Anything unfinished when a session ends is lost in the "wash-up" — the rushed final days before prorogation. That is why ministers sometimes accept amendments they dislike: half a bill is better than none.
Holding a new government to account
Prime Minister's Questions runs on Wednesdays at noon for around half an hour. It is theatrical, and occasionally revealing. Select committees are where the substance often sits: cross-party groups of MPs, chaired by colleagues elected by secret ballot, taking evidence from ministers, officials and outside witnesses. Reports published early in a parliament can set the terms of a debate for years.
Urgent questions, opposition day debates and backbench business give the Commons ways to force a minister to the despatch box. The parliamentary party matters too — the 1922 Committee for Conservative prime ministers, the Parliamentary Labour Party for Labour ones.
Outside the chamber there are by-elections, local elections, the devolved governments in Edinburgh, Cardiff and Belfast, and the courts.
A quick jargon buster
- Prorogation: ending a parliamentary session, which kills bills that have not passed.
- Wash-up: the hurried final days before prorogation.
- Salisbury Convention: the Lords' practice of not blocking manifesto commitments at second reading.
- Statutory instrument: secondary legislation made under powers in an Act, usually with limited debate.
- SpAd: special adviser, a politically appointed aide to a minister.
- Red Book: the Budget document.
- Recall: bringing Parliament back during recess, usually for a crisis.
How to follow it all without drowning
Pick three or four bills and follow those properly. Read the primary documents rather than summaries: the King's Speech briefing notes, the Budget, the OBR forecast, committee reports and Hansard, which publishes every word spoken in Parliament. Committee evidence sessions are frequently more informative than the headlines they generate.
Keep a simple note of dates and distinguish three stages: announced, legislated, in force. A surprising number of "broken promises" turn out to be timing arguments. And check who is speaking — a minister briefing journalists is making a political case, not a neutral statement of fact.
Finally, pace yourself. The opening months are noisy by design: a new government wants to look busy, and the news cycle rewards activity over outcomes. The 100-day mark is a useful moment to ask what has actually changed, what is still working its way through Parliament, and what has quietly disappeared. Most of the answers will arrive long after the hundredth day.
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