The Government would recoup around £230 million a year if the winter fuel allowance was taxed, a Treasury minister says.
At the moment the payments of £200 to people over the women's state pension age and £300 to those over 80 are handed out tax-free.
Treasury Minister Lord Sassoon said in a written parliamentary answer that if the payments stayed the same but were subject to income tax, the Exchequer would get £230 million back in each of the next five financial years.
His response came in reply to a question from Liberal Democrat Lord Avebury, 84, who also asked about the amount that would be raised from taxing free television licences and bus passes.
Lord Sassoon said the Government did not have estimates of those figures.