MPs' wages and pensions were the biggest single outgoing
The cost of running the Houses of Parliament fell by more than £30m last year to just under £500m, figures show.
The overall expense for taxpayers in 2008/9 came to £498.4m, down from £531.8m the previous year.
The cost of the House of Commons increased by more than £12m, but the bill for running the House of Lords was reduced by £46m.
The biggest single outgoing for Parliament was for MPs' salaries and pensions, which came to £157.2m.
The total figures include wages for members and staff, building expenses, security and other administration.
In 2008/9 the cost of running the Lords fell from £152.5m to £106.5m.
The reason for this was that the amount spent on what is listed as "other administration costs" went down from £89.8m to £39.8m.
A Lords spokesman said that the 2007/8 accounts included a final payment of £26m towards the purchase of 1 Millbank, a new addition to the Parliamentary estate.
They also included a £23m loss, following a revaluation of the entire Parliamentary estate, a process which is carried out every five years.
However, the total cost of keeping the Commons going increased from £379.2m to £391.8m.
The amount spent on MPs' salaries and pensions rose by almost £6m.
Matthew Elliott, chief executive of pressure group the Taxpayers' Alliance, said: "The cost of Parliament is a far too high, and a massive burden on taxpayers.
"The headline figure looks to have come down but this is because of extenuating circumstances last year rather than any efficiency drive, and the cost of the House of Commons has risen.
"In light of recent scandals, taxpayers will be hoping for a new streamlined and transparent Parliament, where every penny of their money is spent wisely and every effort is made to keep costs down."
The figures come in a written answer from Baroness Royall, the Chancellor of the Duchy of Lancaster, in response to a query from the crossbench peer Viscount Tenby.