TORONTO - After three consecutive years of increases, basic auto insurance rates will soon fall for some Ontario drivers -- but not enough to compensate for the increases of previous years.

The provincial regulator announced Thursday that rates in the province will decrease an average of one per cent starting this September.

The change will affect motorists who are taking out new policies or renewing their current ones. Costs will depend on where consumers live, the type of car they drive and other risk factors.

The last time rates fell in the province was four years ago. Since then, prices have increased each year. Last year was the largest average jump at 8.77 per cent.

The price decreases announced Thursday will range anywhere from 0.01 per cent to more than eight per cent, depending on the insurance company. Customers of some companies will see no change at all.

Government changes implemented late last year are stabilizing the market and driving down rates, said a spokesman for the Ministry of Finance.

"This is early evidence that some of that stabilization is coming into effect," said Andrew Chornenky.

Those changes give consumers lower minimum coverage, and let them opt-in to higher coverage if they want it.

Drivers can choose whether they want to shore up their basic amounts with options like medical rehabilitation, home care, housekeeping or funeral costs after a crash.

The minimum required rehabilitation coverage used to be $100,000. The government reduced that to $50,000, and allows consumers to purchase $100,000 or $1-million options if they wish.

A spokesman for the Insurance Brokers Association of Ontario said the majority of drivers will soon see costs come down.

"Those types of annual increases that consumers have been seeing the past few years will definitely go the other way," said Bryan Yetman.

A spokesman for a group that represents insurance companies said the recent increases were due to higher costs. James Geuzebroek of the Insurance Bureau of Canada said the regulation changes will simplify the assessment process, leading to lower administrative spending.

The savings will then likely be passed on to customers, he said, but not everyone will see a difference.

"There's no such thing as an average customer," Geuzebroek said.

"Some drivers will see decreases, some will see increases, for some they might remain the same."

The provincial government has been under fire in recent months over the increases of past years.

Last year the Financial Services Commission of Ontario, which approves all auto insurance rate changes, allowed two insurance companies to increase their rates by nearly 10 per cent.

Last September, the average Ontario driver was paying $1,362.11 a year on insurance, up 3.6 per cent from the same time period in 2008, according to numbers released by the Insurance Bureau of Canada.

This April, car insurance quote firm Kanetix said rates in Ontario jumped by nearly 12 per cent in the first three months of the year.

By comparison, rates in Quebec and Alberta fell by 4.6 per cent and 1.6 per cent respectively.