Yes, Bet365 is safe to use. The sportsbook provides various levels of firewall and other protections and the sportsbook itself is regulated by each of the state gaming regulations Bet365 is legal in.
For example, Bet365 was taken to court for refusing to pay over 1 million in winnings to a horse bettor in Northern Ireland in 2024. The company refused a payout of 54,000 to a customer in England in 2024, a case which was still ongoing in 2024.