During his time in the position, Sunak was prominent in the government's financial response to the COVID-19 pandemic and its economic impact, including the furlough and Eat Out to Help Out schemes, and the cost-of living crisis.

He outlined five key priorities: halving inflation, growing the economy, cutting debt, reducing National Health Service waiting lists, and stopping the illegal small-boat crossings of the English Channel by enacting the Rwanda asylum plan.

[41]Sunak supported the successful campaign to leave the European Union in the 2016 European Union membership referendum, criticising the EU's immigration laws: "We are discriminating against countries with whom we have ties of history, language and culture"[42] That year, he wrote a report for the Thatcherite think tank Centre for Policy Studies supporting the establishment of free ports after Brexit, and the following year wrote a report advocating the creation of a retail bond market for small and medium-sized enterprises.

In the weeks leading up to Johnson's first cabinet reshuffle in February 2020, a number of briefings in the press had suggested that a new economic ministry led by Sunak might be established, to reduce the power and political influence of the Treasury.

During the meeting, Johnson had offered to allow Javid to keep his position on the condition that he dismiss all his advisers at the Treasury and replace them with ones selected by 10 Downing Street.

The decision to extend the job retention scheme was made to avoid or defer mass redundancies, company bankruptcies and potential unemployment levels not seen since the 1930s.

Concerns were subsequently raised by organisations including HM Revenue and Customs and the Institute for Fiscal Studies about the statement's impact, as well as its cost-effectiveness, while at least one major retailer declined to take advantage of a financial bonus scheme intended for rehiring employees placed on furlough during the pandemic.

[103] During his speech given on 3 November, he said that he felt optimism despite daunting challenges and that by bringing together finance ministers, businesses and investors, COP26 could begin to deliver targets from the Paris Agreement.

I am sad to be leaving Government but I have reluctantly come to the conclusion that we cannot continue like this.On 8 July 2022, Sunak announced his candidacy in the leadership election to replace Johnson.

[107] Sunak launched his campaign in a video posted to social media, writing that he would "restore trust, rebuild the economy and reunite the country".

[110] During the campaign, Sunak pledged to included tax cuts only when inflation was under control, scrapping of the 5% VAT rate on household energy for one year, introducing a temporary £10 fine for patients who fail to attend GP appointments, capping of refugee numbers, and a tightening of the definition of asylum.

A spokesperson for Sunak later said: "The reality is that Truss cannot deliver a support package as well as come good on £50bn worth of unfunded, permanent tax cuts in one go.

To do so would mean increasing borrowing to historic and dangerous levels, putting the public finances in serious jeopardy and plunging the economy into an inflation spiral.

As Sunak predicted, Truss announced large-scale tax cuts and borrowing in a mini-budget on 23 September, which was widely criticised and – after it rapidly led to financial instability – largely reversed.

[120] As the leader of the majority party in the House of Commons, Sunak was appointed as prime minister by Charles III on 25 October 2022, becoming the first British Asian to take the office.

Jeremy Hunt was appointed Chancellor of the Exchequer, and Dominic Raab was also re-appointed as deputy prime minister and Justice Secretary, he later resigned from these roles in April 2023 and was replaced by Oliver Dowden.

[124][125] Sunak's last cabinet reshuffle in November 2023 saw the return of former prime minister David Cameron to government following a seven-year absence from frontline politics, replacing James Cleverly as foreign secretary.

[143] On 12 December 2023 Sunak secured a government majority of 44 for the Safety of Rwanda Bill, despite the opposition of all other parties and abstentions from members of the European Research Group.

[155] Sunak was faced with the task of rebuilding the Conservatives' reputation which had been significantly damaged by the controversies and scandals of the previous year and the Truss ministry.

on 11 June, addressing the economy, taxes, welfare, expanding free childcare, education, healthcare, environment, energy, transport, and crime.

[167] On 6 June 2024, the 80th anniversary of D-Day, Sunak was heavily criticised for leaving commemoration events early to do an interview with ITV,[168][169][170] including by veterans.

He also offered support to the incoming prime minister Keir Starmer, saying he was "a decent, public-spirited man" he respected and expressed hope he would be successful.

[186] While he respected Starmer's decision to scrap the Rwanda asylum plan, Sunak said that there needed to be an alternative deterrent, otherwise "a large number of those who crossed the Channel illegally will end up remaining here".

[200][201][202] In an Ipsos MORI poll in September 2020, Sunak had the highest satisfaction score of any British chancellor since Labour's Denis Healey in April 1978, and was widely seen as the favourite to become the next Conservative leader.

[232] Reporting around this time also revealed that Sunak had continued to hold United States' permanent resident (green card) status he had acquired in the 2000s until 2021, including for 18 months after he was made chancellor, which required filing annual US tax returns.

[236][237][238][14][239] In April 2022, it was reported that Sunak and Murty had moved out of the flat above 10 Downing Street to a newly refurbished West London home for domestic reasons.

[242][243][244] In April 2022, amid the Partygate scandal, Sunak was issued a fixed penalty notice by the police who believed he had committed offences under COVID-19 regulations by attending a birthday gathering for Boris Johnson on 19 June 2020.

[245][246] After receiving the penalty notice, Sunak said he was "extremely and sincerely sorry" for the hurt caused by him attending the party, and that he respected the police's decision to give him a fine.

[247] In January 2023, Sunak was issued a fixed penalty notice by Lancashire Constabulary after a social media video of him failing to wear a seat belt in a moving vehicle was published.

[192] Speaking about his childhood during the 2024 general election campaign, Sunak said his parents "wanted to put everything into our education and that was a priority" and that he didn't have Sky TV growing up.