Recent PMs have moved into the apartment above number 11, while the chancellor has lived in the slightly smaller lodgings at number 10.
Along with a rent-free property, which other perks will the new PM get as the British public faces a cost of living crisis?
Ms Truss will also be allowed to stay rent-free at Chequers, a stately home that has been used as a country residence by successive prime ministers.
Chequers was gifted to the state by Sir Arthur Lee in 1917, but the Cabinet Office pays an annual "grant-in-aid" as a contribution to staff salaries and maintenance.
In 2020/21, the office paid £916,000.
Currently, there is no public information on whether prime ministers' energy bills are paid for by the taxpayer.
As an MP, Liz Truss was previously allowed to claim expenses for utility bills on a second home.
However, this support is only available to those who a) aren't MPs in London b) don't occupy ministerial residences, like 10 and 11 Downing Street.
As Ms Truss now falls under the second category, she can no longer expense her utility bills under this scheme.
However, this does not necessarily mean she will foot them herself.
In response to numerous Freedom of Information requests, the Cabinet Office did not rule out that PMs are entitled expense their bills.
What is definite, is that prime ministers must pay tax for electricity, heating and maintenance.
As PM, Mrs Truss is entitled to a salary of £75,440. But that’s on top of her salary as an MP, which is £81,932.
Therefore, her combined income amounts to £157,372.
Ms Truss will have to pay council tax on her flat. Both 10 and 11 Downing Street apartments are in Westminster City Council's band H, which means the charge for 2021-22 is £1655.12.
Maintenance and furnishing
To cover costs associated with maintaining and furnishing the Downing Street flat, prime ministers receive an annual allowance of up to £30,000 from the public purse.
Boris Johnson came under fire following claims he had secretly asked Tory donors to foot the £112,000 bill for the lavish revamp, which far exceeded the official £30,000 allowance.
When asked whether she would keep Boris Johnson’s No 11 Downing Street flat decor, Ms Truss told LBC she believed in “value for money”.
The cost of any food and groceries eaten at the flat is met by the prime minister.
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