As the Liberal Democrat leader launches the party's local election campaign, he will lump the Tories together with Labour and claim both have a record in local government of waste and inefficiency.
The attack marks the start of what is expected to be weeks of tough campaigning ahead of the May 2 poll.
Mr Clegg will tell voters in the party's Cornish heartlands: "Difficult decisions will need to be made in local government, just as in national government, and people understand that. But they - rightly - expect that their representatives should make the fairest possible decisions.
"Next month, in wards across the country, people will be confronted with the same choice. Despite all their stated differences, a vote for Labour or the Tories will be a vote for the same thing.
"Their record in local government shows that even when millions of families are feeling the pinch, they'll both squander taxpayers' money on waste, inefficiency and their own vanity projects.
Mr Clegg will highlight changes to the personal tax allowance - a Lib Dem 2010 election pledge - that came in over the weekend which mean that no one pays any tax until they earn more than £9,440.
He will claim the Government has "asked for a bit more from those who can afford it" and will pledge to continue to fight for the introduction of a mansion tax.
"We've increased capital gains tax; introduced a higher rate of stamp duty and a £12.5 billion banking levy; we've closed loopholes and capped tax relief to stop the very rich from gaming the system. And the Liberal Democrats will continue to argue for our mansion tax."