Yes, they are, and we recommend that all sports gamblers accept sportsbook promos whenever they're offered. The best online betting sites have welcome bonuses (aka signup bonuses) for new players and account reload bonuses for returning players, on top of special event bonuses for March Madness, the World Series, the Super Bowl, and so on. Referral bonuses are also on the table when you get a friend or acquaintance to sign up. All online sports betting bonuses come with rollover requirements to be aware of, but these are fair and easy to meet across the board. Typically, sportsbook promo rollovers are set at 5X or 10X at most sites. Here's what that means: Let's say you select a 50% deposit match bonus with a 5X rollover and put $100 into your account. This means you'll have $150 credited to your bankroll. The 5X rollover simply says you must gamble a total of $750 before you can withdraw any free bet winnings. For even the most casual bettors, this is literal free money!