She says the tax cut from 4.5 per cent to three per cent by 2016 would cost the treasury about $90 million a year.
Horwath says that would help cushion the blow of a higher minimum wage, which she is pledging to raise to $12 an hour, also by 2016.
She says the lost revenue from the tax cut will come from finding efficiencies and savings.
Horwath says the tax cut addresses inequality in Ontario while still allowing small businesses to create jobs.
She heads to Sarnia later today.