Income tax and national insurance will be merged in what will be a central element of the Conservatives' election manifesto, according to reports.
Under the merger basic rate income tax payers would pay 32%, compared to 20% income tax today, and higher rate taxpayers would pay 52%, up from 40%.
The paper said the party was actively considering the move, but had concerns that merging two computer systems could create an IT disaster.
The move would simplify the tax system, but there are also fears that the party would appear to be increasing taxes, The Times reported.
Income tax generated £152 billion for the chancellor last year, while national insurance raised £104.5 billion.