While signing up for sports betting in legal states is relatively easy, understanding the rules of official betting can be a bit more difficult. This article covers the basic information you need to know about betting on MLB games, NBA and NHL action, futures markets, boxing odds, and more.

For most bets to have action, they must meet the requirements of a sportsbook’s definition of an “official game.” In the case of baseball bets, the game must reach its designated point, often eight innings. For player props, bets are considered official if the specified player meets the requirements set by the sportsbook (typically one pitch thrown for pitchers or one plate appearance for position players). If a bet isn’t considered an official game, then it may result in a refund.

Many people who bet on baseball don’t realize that there are certain limits to how long a game can last. Most MLB games are shortened or suspended due to inclement weather, which can impact the over/under and moneyline bets. To have action, bets must take place at an official MLB book and go at least 8.5 innings.

The NHL does not have a stated policy against sports betting, but their players are forbidden to gamble on any NHL game while at a team or league facility. This rule is outlined in the league’s collective bargaining agreement. However, players can bet on non-NHL events at legal sportsbooks, but must sign a statement acknowledging the gambling rules spelled out in their CBA.