Benefits for young people will be targeted by the Tories as they seek to cut another £25 billion off public spending, George Osborne has indicated.
The Chancellor played down the prospect of means-testing handouts for pensioners, such as winter fuel payments and free television licences.
But he insisted "substantial" savings would still be needed from welfare after the general election to eradicate the deficit.
The comments came ahead of a speech in which Mr Osborne is due to brand 2014 the "year of hard truths", warning voters that only further austerity measures can pay for tax cuts and better job prospects.
Prime Minister David Cameron committed the Conservatives yesterday to retaining the triple lock on the state pension, which means it rises by whichever is higher of inflation, average earnings, or 2.5%.
Speaking on BBC Radio 4's Today programme, Mr Osborne suggested that protection for other universal pensioner benefits would also be kept.
"These pensioner benefits are something we have protected through this parliament," he said.
"We made a promise, it is a promise based on values. A value of supporting people who have worked hard and saved hard all their lives.
"Those values have not changed.
"We haven't written our manifesto yet, but if you were going to be looking for savings in welfare, pensioner benefits is not the place I would first turn to. I would look at housing benefit for the under-25s.
"There are plenty of people listening to this programme who cannot afford to move out of their home.
"But if you are on benefits, you can get housing benefit under the age of 25.
"There are people, for example, on incomes of £60,000-£70,000 living in council homes. I would look at that issue."