Sports Betting In California The path to legal sports betting in California appears to be a long one. Many expected Cali to be one of the first States to legalize both online and offline sports betting after the Supreme Court Case win for New Jersey last year. That hasn’t happened yet, though. So, when can we expect sports betting legal in California? Is Online Sports Betting Legal In California? Sports betting in California is not legal. Not yet, at least. An amendment to the constitution is due to be discussed and voted on at some point in 2020.