League Rules

NWIBL follows MLB rules with modifications for adult amateur play

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Quick Reference Guide

Wood Bats Only

All bats must be solid wood or approved wood composite (BBCOR certified). No metal bats allowed.

Age Requirements

18+ Division: Must be 18 or older. 30+ Division: Must be 30 or older. 60+ Division: Must be 60 or older.

Game Length

Games are 9 innings or 2 hours and 30 minutes, whichever comes first. No new inning starts after time limit.

Rosters

Teams may carry up to 25 players on their roster. Minimum 9 players to start a game.

Player Conduct

Zero tolerance for disrespecting umpires, teammates, opponents, or fans. Ejections result in automatic suspension.

Equipment

Proper baseball attire required. Metal cleats allowed. Catchers must wear full protective gear.

Detailed Rules

Eligibility & Registration

  • All players must be registered and have a signed player contract on file
  • Players must meet age requirements for their division
  • NCAA eligible players may participate (league is not paid)
  • Former professional players welcome in all divisions
  • Player fees must be paid before first game

Game Rules

  • MLB rules apply unless otherwise specified
  • Designated hitter (DH) may be used
  • Courtesy runner allowed for catcher with two outs
  • Slide or avoid contact rule in effect at all bases
  • Intentional walks may be declared
  • Mercy rule: 15 runs after 5 innings, 10 runs after 7 innings

Pitching Rules

  • No pitch count limits for adult divisions
  • Balks will be called per MLB rules
  • Pitchers removed from mound may not return to pitch in same game
  • No quick-pitching allowed

Conduct & Sportsmanship

  • Respect umpires, opponents, teammates, and fans at all times
  • No arguing balls and strikes
  • Ejected players must leave the field and stands immediately
  • Ejections result in minimum 1-game suspension
  • Fighting results in minimum season suspension
  • Alcohol prohibited in dugouts and on playing field

Forfeit Rules

  • Teams must have minimum 9 players to start
  • Teams have 15-minute grace period past scheduled start time
  • Borrowing players from other teams allowed with league approval
  • Forfeiting team responsible for umpire fees

Playoffs

  • All teams qualify for playoffs
  • Best-of-3 series format
  • Seeding based on regular season record
  • Tiebreakers: Head-to-head, run differential, runs allowed
  • Players must have appeared in 6+ regular season games to be playoff eligible

Player Code of Conduct

NWIBL is committed to providing a safe, competitive, and enjoyable environment for all participants. Disrespect towards umpires, opponents, teammates, or fans will not be tolerated. We expect all players to represent themselves and the league with integrity both on and off the field.

“Play the game the right way. Respect the game, respect your opponents, respect the umpires.”

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