Liz Truss would be line for a "golden goodbye" of more than £18,000 if she is forced out of office or resigns under government rules.
All government ministers are entitled to a quarter of their annual salary as a lump sum if they quit or leave office – with no minimum qualifying period in office.
The rule means that if the prime minister is successfully challenged she will be entitled to the cash, even if Tory MPs swiftly decide that appointing her was a mistake.
Conservative MPs are openly calling for the PM to go after just a month in office, with one apparently obliquely referring to her premiership as a "dumpster fire".
The PM was forced to sack her first chancellor Kwasi Kwarteng for implementing a budget largely composed of her own leadership election pledges – after it sent financial markets haywire and interest rates soaring.
Mr Kwarteng himself was been urged to reject a similar payout, which he is entitled to despite being in the job for just a month.
As an outgoing chancellor he could claim £16,876 in leverage pay - which more than double the amount he was actually paid in salary during his short tenure.
SNP MP David Linden, who represents Glasgow East, urged the former Treasury boss to "do the right thing and refuse to accept the Ministerial severance payment".
In the summer, when ministers resigned from Boris Johnson's cabinet en masse, they racked up total entitlements of more than £200,000 in severance pay – though some said they would not take it.
The prime minister is paid a total of £164,080 a year, of which £79,936 is for their role as PM and the rest as an MP.
Boris Johnson was also in line for the payout, and urged not to take it.
