Softball Regulations


The Intramural sport convener may modify these rules at their discretion. The Intramural sport convener and officials have the discretion to rule on any matter not covered by these rules.

Click here for Intramurals eligibility rules.

Number of Players

• The ideal number of players on the field is 10 for slo-pitch and 9 for three-pitch.
• The maximum roster size is 21 (including a minimum of 3 of each gender for coed leagues). 
• The minimum number of players required to avoid a default is 6 for 3-pitch, and 7 for Slo-pitch. Teams that do not have six players (3-pitch) or 7 players (Slo-pitch), who are registered on the IMleagues roster, ready by ten minutes after the official starting time will receive a default. 
• Co-ed games require a minimum of 3 players of each gender on the field at all times one of which (of each gender) must play an outfield position and one of which (of each gender) must play an infield position other than catcher, the third may play any position provided the preceding requirements have been satisfied. If a team only has 2 players of one gender then one must play an outfield position and one must play an infield position other than catcher, a team may not replace the missing person with a person of the opposite gender therefore they must play short one fielder at a position of their choice (i.e. catcher, outfielder etc.). 

Slo-pitch: If a team has only 2 players of a particular gender they can play with a ratio of 7:2 (i.e. a max of 9 people on the playing surface, you may not replace the missing person with someone of the opposite gender), and they will bat with an automatic out every time the missing “third” player should be batting. 

3-pitch: If a team has only 2 players of a particular gender they can play with a ratio of 6:2 (i.e. a max of 8 people on the playing surface, you may not replace the missing person with someone of the opposite gender), and they will bat with an automatic out every time the missing “third” player should be batting. 

*Teams with less than 2 players of a particular gender at any time during the game (including injury or ejection) will be automatically disqualified.

PLEASE NOTE: Open leagues have no minimum requirement for either gender.

The Game

A. HOUSE RULES In general, our rules are governed by NSA. Please see our house rules below for exceptions. Unless specifically stated, the following rules apply to 3-Pitch and Snow-pitch, as well as Slo-Pitch.

Game Length and Mercy Rules

The game will consist of 7 innings or a 60 minute period; no new inning will start 10 minutes prior to end of the time slot.
II. A final score will stand if a game is cancelled due to weather or time constraints after 4 innings or 4 1/2 if the home team is ahead.
III. Each inning shall consist of 3 outs or a maximum of EIGHT runs. The 7th inning, and only the 7th inning, of a game is an open-ended inning with no cap on runs.
IV. Games are declared completed if either team is ahead by 15 runs or more at any time after the completion of the fifth inning: Mercy Rule in effect. (i.e. Home team has batted, or visiting team has batted and home team is ahead).

Batting Order

Teams must bat the entire squad in the batting order, however a player does not need to play a defensive position in order to be present in the batting order.
II. In all Coed leagues, the batting sequence must alternate gender every third batter. Never can three batters of the same gender bat sequentially. The penalty for such an infraction is the batter being called out, and all runners returning to their original bases once the batter contacts the ball.


A standard situation which arises in co-ed play is having too many of one gender to make an alternating order. The easiest solution is to create two separate line ups, for example a team with 8 males and 3 females. The female batters keep their order and cycle into the spots labeled “female.”

1 Mark

1 Karen

2 Steve

2 Stacey

3 Female (Karen)

3 Sheena

4 Bryan

5 Ahmed

6 Female (Stacey)

7 James

8 Lee

9 Female (Sheena)

10 Jordan

11 Wayne

12 Female (Karen)

III. Batting order is firm at the point where the team has gone through the order once. This means that a player that shows up to the game late, can be added to the line-up only if a person of the same gender in the line-up has yet to bat twice.
IV. In the event of a regular season TIE - the game will be recorded as a tie. In playoffs, International tie breaker rule (start with a runner at second base) will commence right away.

The Batter

When attempting a swing, a batter who steps completely outside the batter's box, in front of or onto home plate will be called out (SLO-PITCH ONLY). The runners must return to their original bases. For the rule to be enforced, the batter’s foot must be on, or directly in front on the ground of, the plate when contact is made with the ball
II. Bunting and “tomahawk” downward swings are illegal in slo-pitch softball. A warning will be issued on the 1st instance to both teams. Upon the 2nd instance by either team an out will be recorded, and all runners will return to their original bases. Players who do not possess the necessary mechanics of a “full swing” at the discretion of the umpire will not be warned or called out for bunting.
III. Any fair ball entering the forest/tall grass (whether rolling or in the air) will be considered a home run.
IV. Thrown bats are very dangerous whether accidental or not. Any incident of a thrown bat will result in a warning being issued to the team, and the next incident for that team will result in the batter being called or depending on the severity, ejection from the game.
V. On a tip foul, the ball must arc above the head of the batter if it is to be caught for an out.
VI. Coed Slo-Pitch - Male Walk Rule - A male batter who is walked on four pitches is awarded second base when followed by a female batter. The following female has the option to hit or take first base.

Base Running

At no time will a base runner be permitted to "run through" a fielder. A runner must slide or give him/herself up. Any undue force will result in an out and could result in automatic ejection from the game as well as suspension.
II. A base runner that illegally interferes intentionally or unintentionally with a fielder attempting to make a play will be called out. If it is an obvious attempt to prevent a double play and it occurs after the base runner is put out, the immediate succeeding base runner shall also be called out.
III. The orange safety bag is used, and is reserved for a batter running to first base. Upon safely touching the orange bag, the runner can continue to run through and cannot be tagged out unless they make steps towards advancing to second base.
IV. Sliding is permitted in Slo-Pitch and 3pitch. In 3Pitch leagues, any slide resulting in contact with a fielder is grounds for ejection as determined by the umpire. Runners must slide to the base, not the fielder. However, if a runner has been forced out while running to second or third base, they cannot interfere with a potential double play and must slide or move clear of the throw to first or second. "Intentional" interference call will be left up to the umpires.
V. The base runner must remain in contact with the base until the batter swings. Failure to do so will result in an out. Only on pitches where a batter swings runners on base will be permitted a courtesy step. There is no stealing or leading off.
VI. Courtesy runners are permitted for players injured during the current game once the batter has reached base. The courtesy runner will be designated as the last batter put out of the same gender. All courtesy runners must be after the batter has attained at least first base. No pinch runners out of the box. The league coordinator as well as officials have the right to refuse play to persons who are deemed too injured to participate or to continue participation for the purposes of safety to themselves and others.
VII. When a ball enters the designated dead ball /out of play territory by way of an errant throw from either the infield or outfield, all base runners will follow the 1+1 RULE: they will be awarded the base attempted, plus one additional base AT THE TIME OF THE THROW. (Ex: runner from 1st base attempts 2nd base, but reroutes to 1st base during play, and is attempting 1st base at time of throw. Ruling: runner is awarded base attempted (1st base), plus one (2nd base).
VIII. Home-Plate Collision Prevention Rule will be enforced. Play at home plate becomes a force-play only, once the runner passes the no-return line. For any play at home plate, the catcher must be positioned on the plate. The base runner's foot must cross the home plate line and be in contact with the ground. A catcher cannot tag out a runner between the lines.
IX. A runner who crosses the “no-return” line must continue to home, any return to 3rd base will result in the runner being called out.
X. A runner touching any part of home plate (3-pitch) or the strike mat (slo-pitch) will be called out.
X1. If a runner comes in contact with a batted ball, when not in contact with a bag, they will be called out.

The Pitcher

All pitches must be delivered from the pitching line, marked 4 ft behind the rubber. The pitcher must have one foot on, or behind, the line when releasing the ball.

3-Pitch Pitching

a) Pitcher is pitching to his/her own team and will never act as a fielder. Members may rotate pitching at any time.
b) Pitcher must get out of the way when a play is being made to the infield, the most common scenario is a ball batted to third base a throw being made to first. The pitcher must move and allow the throw, if interference occurs at the discretion of the umpires, the batter will be called out and runners will return to their original base.
c) A pitcher must make every attempt to avoid a batted ball.  However, if a line drive makes contact with the pitcher “dead ball” will be called and a pitch will be counted against the batter. (i.e. If the contact is made on the first pitch, the batter will receive up to 2 more.  If the contact is made on the third pitch, the batter will be called out.)  It is up to the discretion of the umpire to decide if the pitcher could have avoided the ball or not.  If the pitcher makes intentional contact, the batter will be called out.
d) There is no "arc" restriction on pitches in 3 pitch.
e) A batter gets a maximum of 3 pitches. If none is hit fairly, the batter is out.
f)  Once the ball is returned to the pitcher by the fielding team, or when there is intent by the fielder to return the ball to the pitcher (ie, eye contact or holding the ball up), the play is dead. If the ball is thrown TO the pitcher, and he or she does not catch it, the play is dead. However the pitcher is not required to pick up a ball not intended for them. Ex: Ball is thrown by an outfielder to second base who misses the throw and the ball then runs into the infield near the pitcher, the pitcher does not have to retrieve the ball and it is still live.

Slo-pitch pitching

a)  The pitcher is a member of the fielding team.
b) Pitches will be delivered underhand and have a perceptible arc of a minimum of 6 feet and a maximum of 12 feet the umpire may declare a pitch "illegal" to alert the batter that a pitch will be called a "ball." The batter may still choose to swing at such a pitch, with the result of this being a live ball situation.
c) A "strike" is a pitch that meets the arc criteria and lands on any part of the mat which is placed directly over the plate. Otherwise, the pitch will be called a "ball." The exposed area of the plate in the mat is part of the strike zone.


Free substitutions in the field may take place; this causes no implication to the batting order.
II. The orange safety bag at first base is in use. This bag is reserved for the batter running to first base. If a fielder comes in contact with the orange bag during any time of the runner’s approach, the runner will automatically be called safe.
III. When the batter is running to first, there are no throws allowed from the outfield to first base on the force play. If a batted ball reaches the grass, the batter will be safe at first. The rule does not apply to tag up plays on a runner already at 1st base, or non-force plays at first.
IV. In 3-pitch and Co-ed slo-pitch, markers are placed 50 ft behind the bags in the outfield. Outfielders must remain behind this mark until the batter makes contact with the ball, failure to do so and the fielder becoming involved in play will result in the runners being called safe.
V. Infield Fly:
a) Is a fair ball (not including a line drive):     
    1) When first and second, or first, second, and third bases are occupied.     
    2) That can be caught by any player with ordinary effort.     
    3) Before two are out. 
b) The pitcher, catcher, and any outfielder that positions himself in the infield on the play shall be considered infielders for the purpose of this rule.
1) When it seems apparent that a batted ball will be an infield fly, the umpire shall declare "INFIELD FLY, THE BATTER IS OUT IF FAIR," for the benefits of the runners.
2) The ball is live and runners may advance at the risk of the ball being caught or retouch and advance after the ball is touched, the same as on any fly ball.
3) If the hit becomes a foul ball, it is treated the same as any foul.
4) If a declared infield fly is allowed to fall untouched to the ground, and bounces foul before passing first or third base, it is a foul ball.
5) If a declared infield fly falls untouched to the ground outside the baseline, and bounces fair before passing first or third base, it is an infield fly.
VI. For balls caught in FOUL TERRITORY ONLY, if a fielder catches a fly ball in foul territory (thus a legal catch) and their momentum carries them out of play while maintaining possession of the ball, then runners will not get the automatic advance. The player must immediately bring themselves back in play, and play will continue as with a normal catch in foul territory.


• All players must play in closed toes shoes, no sandals allowed.
• Metal cleats are not allowed to be worn during games
• Bats must be official softball bats of legal size, weight, and shape; conforming to at least one of either ASA, NSA, ISA or USSSA standards and must bear at least one of these regulatory stamps on it denoting its compliance. Wooden bats, bats reading “Little League”, hard ball and Tee ball bats will not be permitted. In any case of uncertainty, it will be at the umpire's discretion as to whether or not a bat is in compliance or not, and whether it is safe to use in our leagues or not.
• Teams must supply their own bat(s)


• In all regular season games, there will be no overtime. Games finishing in a tie will be recorded as such in the standings.


• Format will be determined by the Intramural sport convener based on weather conditions and diamond availability.


Campus Recreation Intramural Sports at Western University holds sportsmanship as “Our Golden Rule of Sport”. Sportsmanship is a great tradition in sports and competition that means playing clean, handling both victory and defeat with grace, style, and dignity, respecting the judgment of referees and officials, and treating opponents with respect. Sportsmanship is a style and an attitude, and it can have a positive influence on everyone around you.

Weather & Playing Field Conditions

• Games will continue to be played during all weather conditions except: if thunder is heard, games will be suspended for 15 minutes. If no thunder or lightning are seen or heard in the 15 minutes, games will continue. If thunder and lightning persist, games will be cancelled and rescheduled, if possible. If lightning is seen, games will be immediately cancelled and rescheduled, if possible.
• Field conditions will be monitored by Intramural staff who may suspend games at any time if they believe the field is unplayable.
• When in doubt, players should expect the game to be played and arrive at the field on time. If games get/are to be cancelled the sport convener will send out a message to those affected as soon as the decision to cancel has been made.

Game Reschedules

I. Cancelled Games (due to weather, space conflicts etc.) will be rescheduled whenever possible to ensure you get the Intramural experience you paid for, however facility availability is limited, and games may not always be able to be rescheduled.
II. Team Requests for a Reschedule - Unfortunately, once our schedules are released online we only make changes due to facility closure, etc.
III. If you need to reschedule a game, email your opponent to gain their permission to a possible rescheduling. Only if the opponent agrees to a change of game time can you email your Intramural sport convener at least 48 hours prior to the game with your request (and proof of opponent’s agreement). Requests will be accommodated when possible, but are not guaranteed. If you wish to swap game times with another game in your division, you must contact the captains of all teams involved in the game swap. The swap can only occur if all parties agree. This must be completed at least 48 hours prior to the originally scheduled game. Proof of all agreements must be sent to the Sport Convener before the game time swap can be executed.
IV. Forfeit the game: If you give at least 48 hours’ notice to your sport specific convener that your team won't be playing and that the game is a ‘forfeit’. You will lose the game, but not your Performance Bond.