The law allows possession of 30 grams or about 1 ounce of flower, which is about as much as an adult can hold in cupped hands. Adults also can have 5 grams of cannabis concentrate for vaping, or 500 milligrams of the psychoactive ingredient THC in cannabis-infused products.
Stores won’t be able to sell more than the legal limit in a single transaction, said Chris Slaby, spokesman for the Illinois Department of Financial and Professional Regulation.
It’s up to individual consumers to make sure they don’t posses more weed than allowed, but there’s nothing to stop them from shopping at multiple dispensaries.
However, most stores expect the supply of marijuana products to run low during the first six months or so of sales. If that occurs, retailers might limit how much recreational customers can buy, or sell only to medical patients.