Ontario’s deficit is projected to be $15 billion in fiscal 2011-12, down from $15.3 billion, and the province is expecting to have a $500 million surplus in five years, the finance minister says.

Dwight Duncan made the announcement Wednesday morning and credited changes in the federal budget, which was introduced on March 29 two days after Ontario’s budget was tabled, for helping lower the bottom line for the last year.

He also said the new surtax on Ontarians who make over $500,000 a year, which the minority Liberal government agreed to in order to win NDP support during Tuesday’s budget vote, will help lower the deficit in coming years and lead to a $500-million surplus by 2017-18.

The two-per-cent surtax on Ontario’s wealthiest will generate $470 million next year, he said.

The new tax bracket and a cap on government spending will help reduce the provincial debt by $3.5 billion in 2017-18.