The prime minister made the pledge in his address to the Conservative party conference in Birmingham. He also promised that the tax-free personal allowance for all workers would increase from £10,000 to £12,500 under a post-election Conservative government.
Cameron claims the changes will result in "30 million people" paying less tax over the course of the next parliament.
"If you work hard, we will cut your taxes, but only if we can keep cutting the deficit so we can afford to do that," he said.
The announcement comes two days after chancellor George Osborne announced in-work benefits would be frozen for two years if the Conservatives are elected with a clear majority.
End to exclusivity clauses in zero-hours contracts
Cameron also backed a ban on exclusivity clauses in his conference speech. The clauses currently allow employers to prevent people on the contracts taking work anywhere else.
The prime minister said if re-elected the Conservatives would fight to increase fairness and reward those "working hard" at all levels of employment.
