The Budget of Her Majesty's Government is an annual budget set by HM Treasury for the following financial year, with the revenues to be gathered by HM Revenue and Customs and the expenditures of the public sector, in compliance with government policy. The budget is one of two statements given by the Chancellor of the Exchequer, with the Spring Statement being given the following year.
Budgets are usually set once every year and are announced in the House of Commons by the Chancellor of the Exchequer. The 2017 budget took place on Wednesday 22 November 2017, and the Chancellor presented the 2018 budget on Monday 29 October 2018. Since autumn 2017 the United Kingdom budget typically takes place in the Autumn in order to allow major tax changes to occur annually, well before the start of the fiscal year. The most recent budget was presented by Rishi Sunak on Wednesday 3 March 2021.
The UK fiscal year ends on 5 April each year. The financial year ends on 31 March of each year. Thus, the UK budget for financial year 2011 would cover the period from 1 April 2011 to 31 March 2012 and is often referred to as 2011–12.
Historically, the budget was usually released in March, less than one month before the beginning of the new fiscal year. Parliament was not expected to take action on a budget for the fiscal year until the summer, several months after the start of the fiscal year. For that reason, Parliament typically passed a "Vote on Account" in early spring that provided continuity of funding into the new fiscal year, up until the point that the new budget was enacted. The spending authorized in the Vote on Account was normally 45% of the amounts already authorized in the current fiscal year, taking into account the Main Estimates and any revised or Supplementary Estimates already approved by Parliament. Legislative action on the proposed budget generally aligned with the executive's original budget request; failure to carry the budget would regarded as tantamount to a vote of No Confidence in the Government.
Since November 2017 the budget was moved to the Autumn, with a view to passing the Finance Act before the commencement of the Financial Year. Votes on Account should no longer be necessary.
Governmental departments submit their funding requests — called "Main Supply Estimates" – to HM Treasury. The government then releases this data in a large consolidated document titled "Central Government Supply Estimates (Budget Year-Following Year): Main Supply Estimates" 
The government reserves the right to submit "Supplementary Estimates" in the spring and winter of a given fiscal year to update its agencies' spending totals for the current financial year and report any governmental re-organizations. When an agency submits a Supplementary Estimate, it is customary to also submit an "Estimate Memorandum" to the agency's relevant oversight committee in Parliament describing and justifying the changes. This condenses two functions – reporting supplemental spending requests and agency re-organizations.
|2021, March||£819 billion||£1.053 trillion||£234 billion|||
|2020, March||£873 billion||£928 billion||£55 billion|||
|2018||£810 billion||£842 billion||£32 billion|||
|2017, November||£769 billion||£809 billion||£40 billion|||
|2017, March||£744 billion||£802 billion||£58 billion|||
|2016||£716 billion||£772 billion||£56 billion|||
|2015, July||£673 billion||£742 billion||£62 billion|||
|2015, March||£667 billion||£742 billion||£75 billion|||
|2014||£648 billion||£732 billion||£84 billion|||
|2013||£612 billion||£720 billion||£108 billion|||
|2012||£592 billion||£683 billion||£91 billion|||
|2011||£589 billion||£710 billion||£121 billion|||
|2010, June 'emergency'||£548 billion||£697 billion||£149 billion|||
|2010, March original||£541 billion||£704 billion||£163 billion|||
|2009||£496 billion||£671 billion||£175 billion|||
|2008||£575 billion||£618 billion||£43 billion|||
|2007||£553 billion||£587 billion||£34 billion|||
|2006||£516 billion||£552 billion||£36 billion|||
|2005||£487 billion||£519 billion||£32 billion|||
|2004||£451 billion||£485 billion||£34 billion|||
|2003||£423 billion||£460 billion||£37 billion|||
|2002||£407 billion||£418 billion||£11 billion|||
|2001||£398 billion||£394 billion||(£4 billion)|||
|2000||£371 billion||£371 billion||£0 billion|||
|1999||£349 billion||£349 billion||£0 billion|||
|1998||£330.1 billion||£332.5 billion||£2.4 billion|||
Differences between the UK and United States:
1. The period of fiscal year. The UK fiscal year ends on 5 April each year, while in the United States it begins on 1 October and ends on 30 September the following year.
2. The person that the budget document begin with. In the UK, Budgets are usually set once every year and are announced in the House of Commons by the Chancellor of the Exchequer. But, in the United States, it often begins with the President's proposal to Congress recommending funding levels for the next fiscal year.
Differences between the UK and European Union:
1. The entity that proposes the budget. Differs with the UK, in the EU, the budget is proposed annually by the European Commission, and reviewed and negotiated by the Council of the European Union (which represents Member States' governments) and the European Parliament (which represents EU citizens).
2. In the EU, the annual budget must remain within ceilings determined in advance by the Multiannual Financial Framework, laid down for a (five to) seven-year period.