Cannabis rules come from the state and from each city and county. This page lists a few basics with the official source for each. When a rule matters to you, read the source.
California basics
- Adults 21 and older can buy cannabis; people 18 and older can buy medicinal cannabis with a physician’s recommendation. (DCC)
- A licensed retailer may sell one adult-use customer no more than 28.5 grams of non-concentrated cannabis and 8 grams of concentrate in a day. (DCC regulations, section 15409)
- You can use cannabis on private property, but not in public places like restaurants or bars, and not where smoking tobacco is banned. (DCC)
- An open container of cannabis while driving or riding in a vehicle is illegal. Keep it in a sealed package or in the trunk. (DCC)
- Cannabis is still illegal under federal law, so you cannot take it across state lines or use it on federal land such as national parks. (DCC)
- Cities and counties can have stricter rules than the state. (DCC)
- Licensed retailers must display their state license in plain sight of the public (DCC regulations, section 15039), and you can look any license up in the DCC license search.
At Elevated SF: everyone must be 21 or older to shop, including medical patients with a recommendation.
In San Francisco
For rules and permits in the city, see the San Francisco Office of Cannabis.
Official sources
- Department of Cannabis Control: Consumers
- Department of Cannabis Control: What’s legal
- Department of Cannabis Control: Medicinal and Adult-Use Cannabis Regulations (revised July 1, 2026)
- California Department of Public Health: Medical Marijuana Identification Card Program
- City and County of San Francisco: Office of Cannabis
A summary for customers, not legal advice. Rules change; the official sources are the final word. Last checked September 25, 2026.