Join the fun today!


From £8 per week

Over 50% join not knowing anyone! We'll place you with similar players looking for a team

Small Group

From £8 per week

Not quite a team but 2-3 friends? Join as individuals & we'll keep you in the same team

Full Team

From £5 per week

With leagues across the city we'll help find a league that works for all your team mates

League info:

  • No.1 social rounders
  • Friendly umpires
  • Levels of play for all
  • All equipment
  • Awesome prizes
  • Post-match bar deals

Battersea Park (Summer)

rounders in Battersea Park (Summer)
Format Day Level
Individual £7.20 p/w
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Team £5.60 p/w
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Canada Water (Summer)

rounders in Canada Water (Summer)
Format Day Level
Individual £8.10 p/w
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Team £6.30 p/w
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Clapham Common (Summer)

rounders in Clapham Common (Summer)
Format Day Level
Individual £8.10 p/w
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Team £6.30 p/w
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Clapham Junction (John Bosco)

rounders in Clapham Junction (John Bosco)
Format Day Level
MixedTuerecreational (indoor)
Individual £7.20 p/w
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Team £5.60 p/w
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Regents Park

rounders in Regents Park
Format Day Level
Individual £8.10 p/w
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Team £6.30 p/w
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Wandsworth Common (Spencer Park)

rounders in Wandsworth Common (Spencer Park)
Format Day Level
Individual £7.20 p/w
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Team £5.60 p/w
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Find out more

  • Leagues typically last 8 weeks and happen at the same venue every week
  • Your game time will vary every week between allocated hrs eg. 7pm and 9pm eg. one week match could be 7pm, next week could 740pm, next week could 810pm etc. We try and give everyone a fair spread of early/mid/late start time across the full season
  • Your game (fixture) times will be sent out to you approx 1 week before the start date of the league
  • Players are able to miss weeks but it is recommended you find a friend/substitute to play instead of you if your team doesnt have enough to field a full team to avoid them incurring a forfeit

Registration process:

  • STEP 1: Select a convenient venue nearby on the night/level that works
  • STEP 2: You can enter any league as an individual, with a friend or two (a small group), or as full team (eg work colleagues or friends outside the office)
  • STEP 3: Pay for the full 8 weeks upfront and we’ll send your full league details 1 week before the league starts

Registration options:

  • Individual Entry– you pay for full season before the league starts eg £65 and then we’ll add you to another team of individuals looking for team-mates of a similar level (Remember 70% of all new members join like this not knowing anyone else!)
  • Small Group Entry – you have a friend or two, but not enough for a full team. You ALL enter as individuals but note down during registration process (Click “Joining with friends”) the names of your friends – and we’ll be sure to put your all in the same team!
  • Team Entry – a captain registers & pays for the whole team and then collects subs/monies back from team-mates. You can add as many players to your team as you wish. Team entry works out quite a lot cheaper per player than joining as individuals. Full payment is in advance rather than weekly to ensure teams are committed to playing every week
  • Outdoor – Maximum of 9 players on the field (Can play with a minimum 6 players)
  • Max 4 male players on field
  • Recommended squad size – 10-12 players



Each game is 40 minutes long and will consist of 4 x 10 minute innings OR an innings will end if all the batting team are out. Extra innings can be played if the first 4 innings are completed before the allocated 40 minutes time slot.


The updated standings will be posted weekly, displaying each teams rank and fixture results.


All eligible teams make the playoffs (teams that have not abused any policies are eligible) in their 8th week. In certain situations teams at or near the bottom of the standings may not advance to the playoffs. Check with GO MAMMOTH league coordinator to see if this applies to your league. Playoffs are single elimination.


Games must start exactly at the designated start time. Teams that arrive late will be penalised (please see forfeits below). Lateness will also result in shorter games and less rounders for both teams.


If a team does not have a full squad (minimum number of original players required according to the rules) at the designated start time a rounder per minute will be awarded for every minute (max 10 minutes), after 10 minutes the game will be forfeited. (A friendly can be played in the result of a forfeit).


In order to participate in the league, each participant must sign the team waiver. Waivers are provided and must be completed and handed in no later than the first night of play. Players not present the first week of play will still be required to sign a waiver with our staff before participating in their first game.


As our Rounders leagues are self-umpired sportsmanship is key. The idea of GO MAMMOTH is to have fun. We hope that all participants keep that in mind when becoming involved. Although the games may become intense, you still can be competitive while maintaining good sportsmanship. With this said, any behaviour deemed unacceptable by staff may result in suspension and/or ejection from a game or the league.


To coordinate and run the league, our refs and/or staff will be available at all times to help the league run as smoothly as possible. If you have questions regarding schedules, policies, rule interpretations, directions to the bar, etc. please ask.



Maximum of 9 players on the field at any on time. However it is permissible to field a team with less than 9 people (minimum of 6 players). No more than 4 male players on the field at any one time in co-ed teams. If a team is short, batters are not allowed to run twice. A minimum of 6 original players are required for the game score to count towards standings. If there are less than 6 original player the game will be considered a forfeit.

Substitutions can only be made at ‘half-time’ following both teams’ first innings.

A ball must be bowled so that it reaches the area between the batter’s shoulders and knees as it crosses the batting line. A no-ball will be called outside these limits.

A ball that bounces before reaching the batting line is a no-ball.

Bowling should be underarm only. The bowler can be male or female.

The batter has only one strike at the ball and must run even if he/she fails to make contact with the ball, unless a no-ball is called.

When a “no ball” is called and the batter does not run – previous batters may not run on to the next post. When either a
“good ball” is thrown or a “no ball” (where the batter choses to run) occurs, previous batters may progress around the field.

A player can run a no-ball and cannot be caught out, but can be out in all other ways. The bowling team will concede a half rounder for every three consecutive no-balls to the same batter. A no-ball from which a rounder or half-rounder will still count towards the total of no-balls.

A batter hitting the ball so that its first bounce is behind the batting line may proceed to first base only and wait until the ball crosses the batting line before proceeding further.

All play ceases when the bowler holds the ball (this is known as a ‘dead ball’).

A batter may not leave or pass a base whilst the ball is ‘dead’, but may continue to the next base, or if less than half-way, have the option of returning to the previous base.

A batter is out if he or she:

–         is caught from a good ball.
–         is stumped out by a fielder.
–         runs to a stumped base before the next ball is bowled.
–         deliberately interferes with the play of the fielders (e.g. kicks the ball).
–         engages in dangerous play while taking a shot.
–         is overtaken by another batter.
–         slides to make ground at a base rather than running.

Once out you must sit/stand away from the playing area.

On all narrow decisions the batter has the benefit of the doubt.

The last batter shall receive up to three good balls and can be caught out on any of these.

Fielders should allow batters an unimpeded run around bases. Fielders on bases should stand inside the diamond to allow a batter to pass.

Rounders are deductible for dissent, and in extreme cases (i.e. abuse of umpire) a player or players may be sent off.

Players or fielders must not slide to make ground instead of running.



  • If the batter reaches the 2nd or 3rd post in one hit, the batting team scores 1/2 a Rounder
  • If the batter reaches 4th post in one hit, the batting team scores 1 Rounder

See indoor rules – click here

Levels of play:

GO Mammoth offers a range of softball leagues at a variety of skill levels from recreational to competitive, we cater to all levels, so you’ll be sure to find a league that matches your skill.

find out more

We love rounders here at Go Mammoth and we think you’ll love playing in our rounders leagues too. If you’re still not convinced here’s 10 great reasons to join one of our rounders clubs today:

  • All equipment provided– No need to bring anything to the pitch, we’ll provide you with everything you need to play in our rounders leagues!
  • Qualified umpires– We have the only rounders leagues in London that provide proper officiating. There will be qualified umpires at each and every one of your rounders
  • Top-notch venues– We have great venues across the capital. Be sure to check out the list of London leagues before registering to find a rounders club near you.
  • Indoor and outdoor– We have both indoor and outdoor rounders clubs across London so you can beat the weather by selecting one of our indoor rounders
  • Individuals welcome– Can’t find a rounders team to play with? Not a problem – just join us as an individual and we’ll find a team for you. All of our rounders leagues are friendly and fun so you’ll fit right in!
  • Affordable– Playing rounders is a low cost way to stay in shape. Compared to the prices of gym memberships, the rounders leagues are very affordable!
  • Beginners welcome – Haven’t played roundersbefore? Its okay, beginners are always welcome! Unlike other rounders clubs in London we don’t expect you to have played before or even know the rules of rounders to join our leagues. Just read up on the basics before you come and our friendly, professional umpires will help you understand the game!
  • Great prizes– We give out prizes! If your roundersteam wins any of our London leagues, you’ll automatically win a prize.
  • Meet new people– Playing in one of our mixed rounders leagues is a great way to meet new people around London. Although some games can get competitive, at the end of the day we’re all here to have fun after a long day of work!
  • Social events – Here at GO Mammoth, we’re all about having fun. Whether we’re on the rounderspitch or at one of the mammoth sponsored bar events, everyone is always having a great time!