The site went live after several weeks of preview testing by members of OLG's rewards program, and allows gamblers to play casino-style games including blackjack, baccarat, single-person poker, roulette and slots.
People can also purchase lottery tickets for Lotto 6/49 and Lotto Max on the new OLG site, which does not yet work with mobile devices. There will be a mobile app developed later as OLG's online site expands with new games.
Players must register to use the new site and establish mandatory weekly maximums for the amount they wish to gamble, but can take the money directly from bank accounts or use their credit cards.
The maximum anyone can deposit in their account each week is $9,900, but OLG expects the average to be about $75-$80.
OLG, which turns over about $1.8 billion in profits to the Ontario government each year, said Ontarians currently spend up to $500 million a year gambling on grey market online sites that are not regulated in the province.
"We are excited to launch PlayOLG, an important milestone in the modernization of gaming in Ontario," OLG vice-president John Wisternoff said in a release.
The Progressive Conservatives said the Liberals are looking for "nickels and dimes in the couch cushions" rather than trying to control their spending.
"I think they're looking to get more money out of the pockets of the most vulnerable people," said PC finance critic Vic Fedeli. "They're looking for new sources of revenue instead of controlling their own spending."
The New Democrats said the Liberal government's gambling strategy isn't progressive and will put vulnerable people at risk.
"If you're in your basement gambling all day because it's easy to do, you're more likely to spend money that you don't have," said NDP finance critic Catherine Fife. "If anybody should take a lesson on that, it should be the Liberal government, which is desperate for revenue."
The cash-strapped Liberal government has promised to eliminate a $12.5 billion deficit by 2017-18.
The NDP also said it had no confidence in OLG's ability to make sure underage gamblers don't get access to its new online site, and warned of social problems down the road from expanded gambling.
"The research and the evidence points to expanding online gambling leading to increased addiction and increased debt," said Fife.
British Columbia, Manitoba, Quebec and all the Atlantic provinces already offer online gambling.
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