He originally sought to build what he called a Cabinet of “all the talents” in an attempt to restore credibility in government after the fall of two prime ministers – Boris Johnson and Liz Truss – in a matter of weeks.
In a February reshuffle, Mr Sunak announced four new or redesigned government departments.
They were the Department for Energy Security & Net Zero, the merged Business and Trade department, the Department for Science, Innovation and Technology and the Department for Culture, Media and Sport.
Some of the biggest jobs have stayed with the same person – such as Home Secretary and Chancellor – but others, such as the defence post, have welcomed new faces.
Here is a look at who’s who in the Cabinet.
Chancellor of the Exchequer
Chancellor Jeremy Hunt was brought in to steady Ms Truss’s ailing government and has been working towards a highly anticipated Halloween fiscal statement.
He was selected by Mr Sunak to keep the keys to No 11 and try to stabilise jittery markets.
The Chancellor is one of the most important roles in government and the economic record is always a key reason for voting at general elections.
James Cleverly was kept on as Foreign Secretary by Mr Sunak, a signal the PM was not breaking entirely with the set-up of the previous two administrations.
On his appointment, Mr Cleverly said he would continue to support the UK’s allies around the world “especially standing with Ukraine”. He has made recent visits to the Middle East and China.
Grant Shapps was moved to defence after being named Mr Sunak's first net-zero secretary. He has also been business secretary, transport secretary and briefly home secretary under Ms Truss.
He is regarded as calm in a crisis, and a skilled, expert communicator with a pragmatic approach.
His predecessor Ben Wallace, who resigned from the post having served for four years, had played a key role in the UK’s response to Russia’s invasion of Ukraine and was a close ally of Boris Johnson.
Deputy Prime Minister
Oliver Dowden, the MP for Hertsmere. He is also Secretary of State in the Cabinet Office and Chancellor of the Duchy of Lancaster.
Suella Braverman was appointed Home Secretary less than a week after she was dropped from Liz Truss’s government over a breach of the ministerial code.
Ms Braverman had been asked to resign for mishandling an official document and left with a parting shot that the government was failing its manifesto pledges on immigration.
Her return only six days later was condemned by opposition MPs, who said it breached Mr Sunak's promise at the door of No 10 Downing Street to restore trust and integrity.
The Home Secretary is one of the key drivers of the government's "stop the boats" policy, under which it is trying to swiftly bring down the number of people arriving in the country via the English Channel in often-unseaworthy boats.
Simon Hart was brought in as Chief Whip to restore party discipline.
Chancellor of the Duchy of Lancaster
Alex Chalk, MP for Cheltenham. He also serves as Lord Chancellor.
Energy Security and Net Zero Secretary
Claire Coutinho, MP for East Surrey, took over from Grant Shapps when he was moved to defence.
Science, Innovation and Technology Secretary
Chippenham MP Michelle Donelan.
Levelling Up Secretary
Michael Gove returned to the Cabinet after being sacked by Boris Johnson. He is also minister for Intergovernmental Relations.
Steve Barclay. He is MP for North East Cambridgeshire.
Leader of the House of Commons
Penny Mordaunt was thrust into the limelight within days of taking up the post due to its prominence when there is a new monarch. She was praised for her roles at King Charles's accession and coronation ceremonies.
Leader of the House of Lords
Lord True is Lord Privy Seal and Leader of the House of Lords.
Business and Trade Secretary
Kemi Badenoch, MP for Saffron Walden. She is also Minister for Women and Equalities, and President of the Board of Trade.
Environment, Food and Rural Affairs
Works and Pensions Secretary
Mel Stride, an ally of Mr Sunak in his leadership contest, was appointed Works and Pensions Secretary.
Culture, Media and Sport
Minister without portfolio
Northern Ireland Secretary
David TC Davies.
Chief Secretary to the Treasury
Paymaster General and Minister for the Cabinet Office
Minister for Development in the Foreign Office
Veterans’ Affairs Minister