NSA Fastpitch Softball Rules

Established in 1982, the National Softball Association (NSA) sets rules and standards for the game of softball as it is played in the United States by youth and adults. Official rules and regulations are reviewed and updated on an annual basis and they cover equipment specifications and the rules of play and conduct.

  1. Softballs

    • The NSA governs fast-pitch softball in the U.S.

      Softballs used to play in NSA-sanctioned leagues and tournaments must be NSA approved. Official balls are 12 inches in diameter, raise-seamed, concealed-stitched or flat-surfaced softballs made of tanned horsehide or cowhide and colored optic yellow. The balls cannot be frozen, chilled, warmed or altered in any other way prior to a game.

    Bats

    • Regulation bats are listed on an NSA approved bat list. They are composite, aluminum or wood and constituted by a "one piece interchangeable barrel," according to the 2010 rule book. Bats can be a maximum length of 34 inches and a maximum weight of 38 ounces. The use of an illegal bat can result in the ejection of a player and her manager from the game.

    Gloves

    • All fielders must wear either a softball glove or a mitt; only catchers and first basemen are permitted to wear mitts.

    Strike Zone

    • A pitch is a strike if the ball crosses any portion of the plate and is between a batter's armpit and the top of his knees.

    Duration

    • A regulation softball game consists of seven innings lasting approximately one hour and 30 minutes. In the event of a tie, a series of sudden death innings will take place. Each team will start a tie-breaking inning with a runner on second base (the last batter of the previous inning).

    Field

    • Regulation fields for adult women can have a distance from home plate to the outfield fence between 200 feet and 225 feet. A regulation field for a men's softball game can have a distance from home plate to the outfield fence of 225 feet to 250 feet. The distance between the bases is 60 feet and the distance from the pitching rubber to the plate is 40 feet to 43 feet depending on the state and league.

    Players

    • A maximum of nine players can take to the field, but teams may play a game with as many as 12 players in their batting line-ups if they exercise the option of having a designated hitter (a player that only hits) or "extra players" (which have a place in the batting lineup and may substitute for players on defense). A batting order must be set before the game and it may not be changed during the game.