An online petition calling for the royals to pay for Buckingham Palace's £369 million refurbishment is gathering pace, attracting more than 130,000 signatures.
The demand, which is addressed to Chancellor Philip Hammond, argues that, rather than taxpayers, the "Crown and its estates should be made to fund its own renovations".
Copywriter Mark Johnson, who started the petition, wrote: "There is a national housing crisis, the NHS is in crisis, austerity is forcing cuts in many front line services. Now the Royals expect us to dig deeper to refurbish Buckingham Palace.
"The Crown's wealth is inestimable. This is, in a word, outrageous."
The major 10-year revamp was announced last week, with officials saying the essential work was needed to avoid the risk of "catastrophic building failure" at the Queen's main residence.
The money will come from a 66% increase in the Sovereign Grant - the funding formula for the monarchy's official duties - for the 10-year period, with the total works estimated to cost £369 million.
One signatory wrote on the petition on the 38 Degrees website: "In a time of austerity and great struggle for many families, this is unacceptable."
The number of signatures now stands at more than 131,600.
Senior Labour MPs have already urged the Royal Family to consider footing some of the repair bill.
Shadow chancellor John McDonnell has said he "certainly wouldn't send the cheque back" if a donation was forthcoming.
Shadow business secretary Clive Lewis went even further, saying he felt the Royal Family could contribute "quite a bit" to the major restoration.
In 1992 - the year the Queen described as her annus horribilis - public opinion turned against the royals amid fears that taxpayers would have to foot the bill for repairs after a devastating fire at Windsor Castle.
More than 100 rooms were damaged in the blaze, which started when a workman's spotlight set a curtain alight.
In the end, the Queen agreed to pay 70% of the £36.5 million costs by opening Buckingham Palace to the public for the first time to generate extra income. It was also announced that she would pay income tax for the first time and cut down the size of the Civil List.
The Buckingham Palace refit will include replacing boilers and miles of cables, pipes and electrical wires when it begins in April next year, subject to Parliamentary approval.
Occupied royal palaces are held in trust for the nation and are not owned by the Queen.