Procedures and Gameplay Rules for Seattle Wiffleball v2.0

Note: Adapted from the rulebook of the Susquehanna River League, Mountaintop, PA.

Last updated April 24, 2022. Recent revisions are highlighted in red.

Seattle Wiffleball Rules

0.00 League Governance
1.00 Eligibility
2.00 Scheduling
3.00 Playoffs
4.00 Game Management
5.00 Umpiring
6.00 Field Setup
7.00 Equipment
8.00 Pitching
9.00 Batting
10.00 At-bats
11.00 Base Running
12.00 Fielding
13.00 Tags and Plugs
14.00 Dead Balls
15.00 Respiratory Epidemic Exceptions

© Seattle Wiffleball 2015-2022

0.00 – League Governance


0.01. Captains. One captain will be selected from each active team. Together, the Captains form the highest authority of Seattle Wiffleball, and may modify this rulebook with a majority vote.

  • A new team's captain is not considered part of the Captains body until the team plays their first league game.

  • If a team's captain is absent for a series, an acting captain will be selected and fulfill all gameday duties, but will not be considered part of the Captains body.

0.02. Commissioner. The Captains will select a Commissioner to organize the league, who will serve until they resign or are replaced by the Captains.

0.03. League Office. The Commissioner may designate members of the League Office, who will assist in organizing the league.

0.04. Fees. League fees are assessed on a per-team basis and are due on Opening Day of a given season. The Captains will set the league fee annually, based on the League Office's projection of funding needs.

1.00 – Eligibility


1.01. Injury waiver. All players must sign an injury waiver for each season. Players under the age of 18 must also obtain a parent or guardian’s signature.

1.02. Sportsmanship pledge. All players must sign a sportsmanship pledge for each season. Egregious acts of poor sportsmanship may be investigated and resolved by the League Office.

1.03. One team per season. Once a player competes for a team in any way, that player is on that team’s roster and cannot compete for another team for the remainder of that season.

1.04. Transfer portal. If a player wishes to play for a different team than in their previous season, they must enter the league transfer portal at least 10 days in advance. This also applies to rookies without previous connections to players in the league.

1.05. Unlimited roster. A new player may be added to a team’s roster at any time during the regular season and there is no limit to the number of players that a team may have on their roster.

2.00 – Scheduling


2.01. Calendar. The season should run from May through August, with spring training in April. This window may be altered by the Commissioner and the Captains.

2.02. Type of schedule. A round-robin regular season schedule will be used if at all feasible, otherwise balanced divisions will be used. Bye weeks will be evenly distributed throughout each team’s schedule, if at all feasible.

2.03. Doubleheaders. All regular season games are doubleheaders. The matchup “home” team will be visitors in Game 1 and home in Game 2. Teams will be “home” in half of their matchups.

2.04. Logistics. Each Captain will submit their team’s availability for the next calendar month at least two weeks in advance, including hard conflicts and soft preferences. The League Office will then send out a draft schedule before releasing a final schedule at least one week prior to the first game of that month.

2.05. Changes to final schedule. Once the final schedule is posted, changes can only be made if all involved Captains and the Commissioner agree.

2.06. Punctual. All series will start at the scheduled time as long as each team has at least four players present. Subsequent games will start shortly after the conclusion of the previous game.

2.07. Severe conditions. If any of the following severe conditions is forecasted for the start time of a series, the League Office will cancel and reschedule it:

  • 0.5” or higher rainfall in the preceding 24 hours

  • Visible lightning or audible thunder in the preceding hour

  • 105 or higher heat index

  • 150 or higher air quality index

2.08. Postponement. Both Captains involved in a series may decide to postpone for any reason. However they must notify the Commissioner of their decision at least 3 hours in advance, and they are responsible for organizing their own makeup games.

2.09. Setup. The first two teams of the day are expected to set up the field, with each team taking half the work. No players should warm up until the field is completely set up.

3.00 – Playoffs


3.01. Playoff series. Playoff series will be three games long. The higher seeded team will be the home team for games one and three.

3.02. Qualifying teams. Six teams will make the playoffs. The top two teams will have byes into the semifinals, while the first round will have the 3 seed play the 6 seed, and the 4 seed play the 5 seed. In the semifinals, the 1 seed will play the lowest remaining seed.

3.03. Tiebreakers. In case of a tie in the standings, the following tiebreakers will be used:

  • Record between tied teams
  • Run differential in all games (capped at 15 per game)
  • Runs scored in all games
  • Runs allowed in all games
  • Run differential in games between tied teams
  • Drawing of lots or Playoff, at Commissioner’s discretion

3.04. Player eligibility. For a player to be playoff eligible, they must have played in two less than half of their team's regular season games. In 2022, this is 8 games for the 20-game season. A player shall earn a game played by meeting any one of the following criteria:

  • Recorded at least one full plate appearance, from 0-0 count to completion.
  • Pitched to at least one batter, from 0-0 count to completion.
  • Defended for three outs in the field.
  • Present when a forfeit is claimed.

4.00 - Game Management


4.01. Pregame meeting. The Captains of each team shall meet prior to the series to exchange pleasantries and review rules.

4.02. Declaring starters. Prior to the first pitch of each game, these four events are to happen in order:

  • Home team declares its starting pitcher
  • Visiting team declares its starting pitcher
  • Visiting team declares its batting order
  • Home team declares its batting order

4.03. Game length. All games will be played to six innings unless called due to forfeit, mercy, or time constraint. Each team gets three outs per inning.

4.04. Forfeit. If one team does not have at least four players present 15 minutes after the scheduled start time of a game, the opposing captain may claim a forfeit if they have at least four players present. If additional games are to be played in the series, and the forfeiting team from game one still does not have four players 30 minutes after the scheduled start time for game one, the opposing captain may claim a forfeit on all remaining series games.

4.05. Mercy.Games will be ended due to mercy if a team is ahead by 20 runs after 2 innings, 15 runs after 3 innings, or 10 runs after 4 or more innings. If the visiting team is ahead, mercy is only in effect if the lead is held at the end of the inning. If the home team reaches the number of runs needed for mercy, the game ends immediately.

4.06. Time constraint. No new inning will be started 1:05 after the start time of Game 1, except by agreement of both Captains. Game 2 will not start a new inning within 10 minutes of the next scheduled series, or 15 minutes after the day’s sunset time.

4.07. Extra innings with ghost runners. Up to two extra innings may be played with a ghost runner on 2nd base. Pitchers will not be charged with a run allowed if the ghost runner scores. The game will be declared a tie if the score is still tied after two innings.

4.08. Suspending. If time constraints (Rule 4.06) or severe conditions (Rule 2.07) make an in-progress game unplayable, the game will be suspended. Suspended games should be halted in between innings to avoid providing an advantage to either team, if at all possible.

4.09. Options for suspended games. The Captains should discuss plans for a suspended game while at the field, and adopt one of the following by 11:59 PM on the date of suspension.

A. Final: If a game is suspended following the conclusion of the third inning, with both teams batting an equal number of times, the game will be declared final unless both Captains and the Commissioner agree otherwise.

B. Replay: If a game is suspended prior to the start of the fourth inning, both Captains and the Commissioner may agree to replay the game in full, with stats from the suspended game not counting.

C. Continue: The game is continued from the exact point of suspension at a later date.

4.10. Continuing rosters. Teams will not be penalized for showing up with fewer players on the day that a suspended game is continued. Additional players may also be added to the bottom of the lineup when the game is continued, regardless of the inning. However the batting lineup must be kept as similar as possible and all pitching regulations still apply to the series.

4.11. Playoffs. In the playoffs, Rules 4.06 and 4.07 do not apply, and Rule 4.08 should only be applied in case of darkness or severe conditions. Extra innings without a ghost runner will be played until ties are broken.

5.00 - Umpiring


5.01. Equal treatment. To maintain a consistent and fair competition, no participant shall receive preferential treatment for any reason whatsoever. All rules, including plugging and fast pitching, must be enforced equally.

5.02. Disputes. When the outcome of a play is disputed, the two captains will consult with their teams, and then come together to resolve the dispute in the spirit of honesty, sportsmanship, fairness, and accuracy. Other players may speak with their captains, but must refrain from arguing with the other team or interfering with the captains discussion. Agreeing to a no pitch or any compromise outcome is permitted.

5.03. Arbiter. If an outcome cannot be settled on, both Captains may defer the outcome of the play to a non-participating third party, such as the active scorekeeper. Otherwise, third parties and fans must refrain from interfering with the umpiring of the game.

5.04. Designated arbiters. In the playoffs, the League Office will provide an arbiter with the approval of both captains, who will be the sole third party consulted by Rule 5.03. In the regular season, a designated arbiter may be requested by agreement of both Captains, but the League Office cannot guarantee that one will be provided.

5.05. Incompleteness. For any scenario not covered in this rulebook, the ruling shall follow Major League Baseball's rulebook.

6.00 - Field Setup

6.01. Baselines. The baselines are 45 feet. A “commit line” is painted exactly halfway between home plate and third base. An “advancing line” is painted exactly one-quarter of the way from first base to second base, and from second base to third base.

6.02. Pitching rubbers. There are two pitching rubbers. The front of the standard rubber is 42 feet from the apex of home plate. The close rubber is 7 feet in front of the standard rubber, 35 feet from the apex of the plate.

6.03. Strike zone. The strike zone is 3 feet tall by 2 feet wide and begins about 17 inches off of the ground. The strike zone is 3 feet behind the apex of home plate.

6.04. Fence. The fence is positioned in three equal linear segments. The left and right field foul poles are 110 feet from the apex of home plate and the alleys are 115 feet from the apex of home plate.

Option 2. The fence is a symmetrical arc such that the left and right field foul poles are 110 feet from the apex of home plate, and center field is 120 feet from the apex of home plate.

6.05. Foul arc. A foul arc is painted 17 feet from the apex of home plate.

6.06. Dead ball circle. An imaginary dead ball circle with a radius of 5 feet is centered around the middle of the standard rubber.

6.07. Out of play lines. Imaginary out of play lines extend from the ends of the backstop parallel to the first and third base lines. If no backstop exists, the out of play lines are approximately 15’ from the base lines. All spectators and players not currently in the field must remain behind these lines at all times.

7.00 - Equipment

7.01. Balls. The only official ball of the league is manufactured by Wiffle Inc. Only balls belonging to the league and stamped with the league logo may be pitched in competition. The league will provide scuffed and unscuffed balls.

7.02. Doctoring. It is legal to play with a ball scuffed by gritted surfaces, but it is illegal to play with a ball cut by a blade, shredded by a grater, or otherwise gouged with a tool. Foreign substances may not be placed on or in the ball.

7.03. Cracks. If a ball has a crack of a quarter inch or more, i.e. halfway through a fin or extending to the seam, it will be removed from play.

7.04. Bats. All bats must be approved by the Commissioner before they are allowed in competition. Nearly all bats designed for wiffleball should be legal, as long as they are not loaded or noticeably larger than the model Loco Bat.

7.05. Tape. Bats may be taped at the handle, but the tape must not add significant weight.

7.06. Field equipment. Fielders must not intentionally use a glove, cap, shirt, or any other object to assist in fielding the ball.

7.07. Safety base. For safety purposes, first base is split into two parts, a white base in fair territory for the fielder to cover and an orange base in foul territory for the runner to run through.

7.08. Spikes. Players may wear rubber spikes. However studded “football” spikes and metal spikes are not allowed.

8.00 - Pitching

8.01. Legal pitch. The pitcher's back foot must be touching the rubber for the duration of the pitch. If a pitcher balks there is no penalty, but they must give the batter time to reset.

8.02. Speed limit. Pitches from the standard rubber should be below 70 mph. Pitches from the short rubber should be below 47 mph. On an overspeed pitch, the batting team may take the result of the play, or add a ball to the count.

8.03. Radar gun. Operating the radar gun will generally be the responsibility of the batting team. However, anyone associated with the league is permitted to gun and enforce the speed limits. The radar gun operator may announce an overspeed pitch at any time. Rule 10.07 may be applied to operators who announce non-overspeed pitches in a distracting manner.

8.04. Switching rubbers. A pitcher may switch the rubber they are pitching from once per game.

8.05. Warm-up pitches. Entering pitchers may throw up to twelve warm-up pitches from the mound. Continuing pitchers may throw up to three warm-up pitches before starting the inning. Entering pitchers must be announced before throwing warm-up pitches on the mound.

8.06. Batter minimum. Entering pitchers must face at least three batters, or complete their half of the inning.

8.07. Closers. Any pitcher who enters at the beginning of the fifth inning or later is considered a closer. A player may pitch in both games of a doubleheader if and only if they are a closer in both games.

8.08. Re-entry. Once per game, a team may re-enter a pitcher who had previously been removed, as long as they did not throw a pitch in any of the batting team's previous six plate appearances. They cannot record a hold or save.

8.09. Playoff limits. The first two games of a playoff series will be treated like a doubleheader. In the decisive game, pitchers who meet either of the following criteria may only pitch three innings of regulation:

  • Started either Game 1 or 2.
  • Entered in relief for more than 2.0 innings in Game 1 and 2 combined.
  • Pitchers may continue without limit if the decisive game goes to extra innings, but the re-entry rules for pitchers still apply.

9.00 - Batting

9.01. Legal swing. Batters must be in the batter’s box when the pitch is thrown. If a batter makes contact while standing on home plate or attempting to bunt, the result is an automatic strikeout.

9.02 Double hit. A ball that has been hit twice on the same swing shall be considered legal.

9.03. Minimum. The batting order must have at least four players.

9.04. Late adds. Prior to the start of the fourth inning, a new player may enter the field or the batting order at any time. New players may be added anywhere after the current spot in the batting order, unless the team has already batted around, in which case they must be added to the end of the batting order. After the start of the fourth inning, a new player may not enter the batting order except as a substitution.

9.05. Re-entry. A player substituted in the batting order may only re-enter in the same spot that they previously exited. A player may re-enter the batting order only once per game.

9.06. Vacated lineup. If a player leaves the batting order without being substituted for, then the vacated spot shall count as an automatic out for the remainder of the game unless the player exited the game due to injury.

9.07. Batting out of order. For a batting out of order call to be made, the fielding team must first wait for the improper batter to finish their plate appearance. After the plate appearance is over but before the next pitch is thrown, they may make a batting out of order call. If the call is correct, then the previous plate appearance will be recorded as an out and the appropriate batter will take their turn at bat. The out will be charged to the team and not a specific player. If the batting team realizes that the wrong player is up to bat before the at-bat concludes, then the correct batter may continue the at-bat and the fielding team may choose to either keep the count as is or reset it to 0-0.

10.00 - At-Bats

10.01. Balls and strikes. The count consists of up to four balls and three strikes. Balls and strikes will be determined by the strike zone placed behind home plate. Any pitch that hits the front plane of the zone or clips its side in flight shall be called a strike.

10.02. Foul tip. There is no limit to the number of foul balls that can be hit with two strikes. However, if a batter with two strikes hits a foul ball that then hits the strike zone in flight, the batter is charged with a “foul tip” strikeout.

10.03. Hit by pitch. If a batter is hit by a pitch, first base is not awarded.

10.04. Batter interference. Batter interference may be called and a strike recorded in the following circumstances:

  • If the batter actively or passively moves any part of their body into the path of a pitch that has a chance to be a strike.
  • If the pitcher declares which parts of the batter’s stance are obstructing the strike zone as viewed from the center of the rubber, the batter declines to change their stance, and one of those parts is struck by the pitch.

10.05. Catching a pitch. If a batter touches the ball while attempting to catch a pitch, it shall be called a strike regardless of its location.

10.06. Ball buckets. To speed up the pace of play, pitchers should keep a bucket of balls behind the rubber. The batting team should also keep a bucket behind the strike zone and collect balls for the pitcher, unless all members of the team are either batting or on base.

10.07. Intentional distraction. The intentional distraction of another player through the use of any sounds or gestures is not allowed. If a member of the fielding team intentionally distracts the batter, then the same protocol is followed as for an overspeed pitch. If a member of the batting team intentionally distracts a fielder, then the batter or base runner, depending upon which is more appropriate to the situation, shall be ruled out and no runners shall advance unless forced.

11.00 – Base Running

11.01. Pinch running. After reaching base, players must run for themselves. Pinch-runners are only allowed in the following situations:

A. An official substitution to the batting lineup.

B. If a player who is on base is scheduled to bat, their spot on base will be taken by the last player to bat who is not currently on base. If the player gets out in their at-bat, they have the option of returning to their spot on base.

11.02. No leads. Leading and stealing are not permitted. If a runner is off base when the batter makes contact with the ball, they are immediately ruled out.

11.03. Tag up. A base runner may legally attempt to tag up as soon as a fielder touches the ball.

11.04. Baseline. The baseline is defined as the direct path between the runner and the base when a fielder attempts to make a play on the runner. The runner shall be declared out if they deviate more than 3 feet from the baseline.

11.05. Running through first. A player running through first base must attempt to touch the foul half of the safety base. They must remain in foul territory or else they can be tagged or plugged out.

12.00 - Fielding

12.01. Legal fielders. A player must be in the batting lineup in order to play in the field. Including the pitcher, a team must take the field with four to six players. Non-pitcher fielders may be substituted at any time.

12.02. Positioning. Defensive players, with the exception of the catcher if one is used, must remain in fair territory beyond the foul arc until the pitch is thrown.

12.03. Catcher. The fielding team may decide to use one of their fielders as a catcher. The catcher must remain directly behind the strike zone until the batter makes contact with the ball. A pitch fouled back over the top of the zone will be considered a pop-up, which can be caught for an out, while a pitch fouled back below the top of the zone will be considered a foul tip.

12.04. No equipment. When the ball is in play a fielder may not use any equipment, such as a hat or glove, to assist in fielding the ball. If the fielder does so and the ball is fair or potentially fair, all runners who were on base will score and the batter will be awarded third base. The scorekeeper will determine if a single, double, or triple shall be recorded. If use of the object may have prevented the ball from going over the fence, then a home run shall be awarded.

12.05. Foul arc is a foul line. The foul arc is treated like the foul lines. If the ball is touching the arc, it is fair.

12.06. Unlimited fielding. Foul territory is unlimited in regards to catching a ball in flight. Runners may still tag up on any caught foul ball.

12.07. Ground rule double. If a fair ball rolls or bounces past the out of play lines or beyond the fence, a ground rule double shall be awarded.

12.08. Buckets are in the field. The buckets and any extra balls are considered part of the field. If a batted ball hits other balls such that it cannot be determined which is the live ball, a dead ball shall be declared and runners will advance two bases.

12.09. First base forces. When covering first base, the fielder must attempt to remain on their half of the base. If it becomes apparent that there is not going to be a play at first, the first baseman must stay out of the baseline between first and second, in case the runner attempts to advance to second.

13.00 - Tags and Plugs

13.01. Tagging. When making a tag, the hand or hands containing the ball shall be treated like the ball itself, as long as the player has complete control of the ball when the tag is initiated. If a player drops the ball while making the tag, the runner is still out.

13.02. Plugging. If a runner is touched by the ball while off base, they are out. Fielders may intentionally throw the ball at runners (“plug”) to get them out. If a player is plugged above the shoulders while running normally within the baseline, they are not out.

  • Running normally means the runner did not jump, duck, dive, slide, or otherwise move their head into the path of the ball.

13.03. Zone tag or plug. Tagging or plugging the strike zone will get a runner from third base out under the following circumstances:

A. If the runner committed to going home by touching any part of their body to the ground on or past the commit line.

B. If there is a force play at home.

C. If the runner failed to tag up at third base, committed to going home, and has not yet returned to third base.

13.04. Dead ball. If a runner is called out by Rules 13.02 or 13.03, the play is dead. Runners who were more than one-fourth of the way to a base other than home shall be awarded the next base. Runners forced as a result of these awards shall advance. If the runner is safe, then the play is still live.

14.00 – Dead Balls

14.01. Dead ball circle. A play is dead once no runner is attempting to advance and a fielder is in possession of the ball with both feet planted inside the dead ball circle. A runner may still attempt to tag up on a ball caught within the circle.

14.02. Runner interference. Runner interference may be called in the following circumstances:

A. If a runner impedes a fielder from making an attempt on the ball.

B. If a runner tries to kick, swat, or catch the ball.

The play is dead and the runner is declared out. All other runners shall return to the last base that they touched. If the batter had not yet reached first base, they are awarded first base and only runners who are forced shall advance.

14.03. Struck while on base. If a runner is inadvertently touched by a hit ball in fair territory while standing on base, the ball is dead and the batter is awarded a single. Only runners who are forced shall advance.

14.04. Out of play. If a ball is thrown out of play and the defense calls “out of play”, the play is dead. Runners who were more than one-fourth of the way to a base other than home shall be awarded the next base. Runners forced as a result of these awards shall advance. After those awards, all runners are awarded their next base. If the defense does not call “out of play” then the play is still live and runners may advance at their own peril.

14.05. Infield fly. If a ball is hit in the air with runners on both first and second base with fewer than two outs, the batting team may call an “infield fly” at their discretion. The call must be made while the ball is still aloft, and it must be loud enough for all players on the field to hear. If the fielding team calls the infield fly or if the batting team calls it in a non-applicable situation, then Rule 10.07 may be applied.

15.00 – Respiratory Epidemic Exceptions

15.01 This section contains rule modifications to protect players from a respiratory epidemic, as experienced during the COVID-19 pandemic. If any outdoor mask mandate is in effect at the field, either captain may instate any of these amendments.

15.02. All players must have face coverings that cover the mouth and nose, referred to here as masks. Pitchers and batters need not wear masks, but infielders are expected to wear masks with runners on base, as are baserunners. Players should also wear masks at the request of teammates or opponents.

15.03. Rule 1.09 is amended. A verbal display of sportsmanship is expected in place of handshakes.

15.04. An exception is made to Rule 7.06 and Rule 12.04. Players may wear batting gloves in the field for sanitary reasons.

For any scenario not covered in this rulebook, the ruling shall follow Major League Baseball's rulebook.