Angela Rayner has been accused of "staggering hypocrisy" over taxpayers having to front council tax for her government-owned home in London.
The bill for the flat in Admiralty House is paid for by the public as it is the Deputy Prime Minister's second home.
Ms Rayner's primary residence is listed in her Ashton-under-Lyne constituency, while her office is 200 miles away in London.
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With her apartment in London - a grade I-listed building in Whitehall - listed as her second home, the bill of £2,034 a year is covered by the Government, The Telegraph reports.
However, it would double to £4,068 under a new premium placed on second homes - which came into place in April.
The Tories have claimed Ms Rayner's Ashton-under-Lyne home is not her primary residence, given her Deputy Prime Minister role.
"It is staggering hypocrisy for the Deputy Prime Minister to push punitive new taxes on family homes while apparently avoiding those same taxes herself," Conservative Party Chairman Kevin Hollinrake said.
"One rule for Rayner, another for everyone else."
Angela Rayner's primary residence is listed in her Ashton-under-Lyne constituency
| PAMr Hollinrake said there was "now serious questions about the role of government ministers in this apparent cover-up".
"Why were these tax perks not disclosed honestly to parliament," he said.
"“And with the revelation of a third property in Hove for weekend use, it is only right to ask whether Admiralty House should in fact be treated as her primary residence and whether she owes the tax liabilities that come with it.”
Supporters of Ms Rayner say she is paying the right amount of tax.
James Cleverly led the Conservative charge against Ms Rayner, saying she was 'responsible for housing policy, yet she won't even be straight about her own'
| GB NEWSHowever, her properties were the subject of criticism over the weekend.
It emerged that she had bought a £700,000 home in East Sussex this year.
The home is in addition to Admiralty House - which comes with her ministerial position - and a £650,000 house in Ashton-under-Lyne.
It comes as Nigel Farage appeared to put up a surprising defence of the Deputy Prime Minister as he criticised top Tories over their reaction.
Despite Ms Rayner just last week accusing Mr Farage of "failing young women" by opposing the Online Safety Act, the Clacton MP instead swiped at Shadow Housing Secretary James Cleverly.
Speaking at a press conference in Oxfordshire, the Reform UK leader said: "Isn't it funny that the residence that Angela Rayner is living in in London is now coming under criticism from James Cleverly?
"He wasn't complaining when Michael Gove was living there.
"So, it's just party politics. If Angela Rayner had been tremendously successful in business and managed to acquire a property portfolio and done it properly, then jolly good luck to her.
"This whole sort of hair shirt approach, most of the press want politicians in sackcloth and ashes, would like all of us to vegan and give up drinking. Well, it's not happening here."
Mr Cleverly led the Conservative charge against Ms Rayner, saying she was "responsible for housing policy, yet she won't even be straight about her own".
He said: "Time and again she's been asked to declare exactly what properties she owns and where she pays council tax, and time and again she's dodged those questions.
"We've done everything possible to get answers, but she still refuses to come clean.
"That matters, because this is the same Deputy Prime Minister who's hiked taxes on family homes across the country.
"If she's not prepared to be open about her own affairs while taxing everyone else, the public will wonder what she has to hide."