Most people believe it is too easy for the rich to avoid paying a fair level of tax, even in households with a six figure income, according to a new report.
The TUC said its research showed that only 7% of the public thought that the balance between tax paid by the rich and poor was right.
The survey of 2,100 adults revealed that only 13% of households with a six figure income were not critical of the tax system.
Three out of four of those polled agreed it was too easy for very rich people to get out of paying a fair level of tax.
A majority also complained it was too easy for big companies to avoid paying tax, according to the survey.
TUC general secretary Brendan Barber said: "An astonishingly large majority of people think the tax system is unfair and that it is too easy for big companies and the well-off to get out of paying fair taxes.
"The public knows that every pound the rich do not pay has to be made up by ordinary peoples' taxes or by cuts in public services.
"Creating a fairer tax system does not mean a higher tax bill for ordinary workers. Instead, clamping down on tax avoidance and closing the loopholes enjoyed by the super-rich will put extra revenue into ordinary peoples' pockets or pay for our hard-pressed public services.
"The millions of voters who are feeling the pinch from rising prices and mounting bills will welcome a Government stand for tax justice."
Disclosure: I am speaking alongside Brendan Barber at a TUC organised conference tonight asking the question "Is it time for tax justice".