TORONTO - Ontario's New Democrats promise to stop fare hikes for public transit if elected to government in the fall election by subsidizing the system across the province.

"People who rely on public transit, depend on public transit, shouldn't be slapped with fare hikes every time they turn around," said NDP Leader Andrea Horwath.

Horwath said Wednesday that if elected, an NDP government would match municipalities' operating costs for transit dollar for dollar, returning the province to a subsidy program that was in place until the Conservatives decided to axe it in 1998.

To receive the funding, municipalities would have to freeze transit fares for four years.

The program is expected to cost $375 million a year on top of the $320 million already handed out for the gas tax, amounting to about $700 million a year. It would be phased in over four years.

The NDP notes that the Toronto Transit Commission funds 70 per cent of its operating costs through fares, compared to 55 per cent in New York City or Montreal.

The plan would apply to buses, subways and streetcars across all cities, but not to commuters using GO Transit.

The governing Liberals have for their part floated the idea of offering refunds for GO riders if their train is more than 20 minutes late.

But Horwath said her party would hold off on making any decisions around GO service until it sees recommendations from Metrolinx, the provincial-funded agency that runs GO Transit.

"This right now is speaking to municipal transit systems, and the fact that in communities across the province, people are struggling to pay the bills and they're seeing their transit fees increase," Horwath said.

"We want to provide not only relief to those transit fee increases but also some relief to municipal budgets."

Transportation Minister Kathleen Wynne said that at first glance the NDP numbers didn't seem to add up, noting the kind of investment the party was talking about would be closer to $1 billion.

"There was nothing about expansion, there was no conversation about what kind of capital dollars would go into municipalities to help them build more transit and that's what people are asking for," Wynne said.

Horwath said her party would be talking more about how to help municipalities with their capital plans in months leading up to the election.

The NDP will unveil the bulk of its platform at a pre-campaign convention this weekend in Toronto, but has already promised to raise corporate taxes, cap gasoline prices and remove ambulance fees for people who need to be transported to hospital.

More than 750,000 Ontarians take public transit to work, according to the NDP, as well as between one-in-five and one-in-four Toronto and Ottawa-area residents.

According to Statistics Canada, the average household spent $375 a year on public transit in 2007, up 80 per cent from $209 a year in 1997.