Oregon reached a major milestone on Thursday by becoming the third U.S. state following Colorado and Washington to legalize recreational marijuana sales.

Starting on Thursday, more than 250 medical marijuana dispensaries in Oregon began selling pot to recreational users over the age of 21, reports The New York Times.

Back in July, it became legal for adults to grow, possess and use marijuana in Oregon. However, until now, only medical marijuana card holders were allowed to legally buy it. Now the dispensaries have been given the green light to sell pot to the general public, reports the Northwest News Network.

Under the new law, Oregon adults can also buy up to a quarter-ounce or seven grams of dried pot along with seeds and immature plants. However, a wider range of products, including edibles, will not go on sale until 2016.

Last year, an overwhelming amount of Oregon voters approved the law to end state sanctions for use and possession of pot. Alaska residents also voted to legalize the drug in 2014, while voters in Washington and Colorado passed legislation to allow legal sales of the drug in 2012.

Federal law still prohibits marijuana use for any purpose, although 23 states permit cannabis use for medical purposes. Ohio voters can expect to vote on legalization measures in November, while several other states will face the same dilemma in 2016.

For the remainder of the year, recreational pot sales will be untaxed, but officials say that likely change next year.

"I'm worried about the 25 percent tax coming in January, but for a $10 gram that's only a bit over $2 more. I think it might be worth it for the quality," said Juliano Hamana, 24, according to Reuters.

"You can get all the best strains from Oregon, which can make this into a top tourist spot," said Sue Vorenberg, editor of the Cannabis Daily Record.