Based on the World Bowls Laws of the Sport — Crystal Mark Fourth Edition. All 10 laws explained clearly.
A "set of bowls" means four bowls of the same manufacture, identical in size, weight, colour, bias, and where applicable, serial number. Only bowls from the same set may be used. Any objection to the bias must be raised no later than the sixth end.
Must have bias not less than the master-bowl, bearing a clearly legible WB, WBB, IBB, or BIBC stamp dated 1985 or later. Non-composition bowls must bear a stamp not earlier than the year in which they are being used.
A solid white or yellow sphere between 63mm and 64mm in diameter, weighing 280–290g. Must bear a World Bowls or national association approval mark.
Rectangular, 600mm × 360mm, made of rubber or similar. Must be plain in colour and free from raised markings that could affect a bowl's path.
A bowling green must be between 31 and 40 metres in length in the direction of play. It must be flat and level, usually square in shape, with a ditch at each end.
The green is divided into individual playing rinks, each 4.3–5.8 metres wide. Marked by boundary pegs or strings. Players must not step into adjacent rinks during play.
Present at each end of the green, typically 200–380mm wide and 50–200mm deep. Bowls entering the ditch are generally dead unless previously marked as touchers.
The raised area behind the ditch. Must be high enough to stop bowls. No object may be placed on the bank to assist a player, except the jack position marker.
Placed centrally along the rink centre line before each end. The mat line must be at least 2 metres from the rear ditch. Once the jack has been cast, the mat must not be moved unless accidentally displaced.
The jack must come to rest at least 25 metres from the mat line and within the side boundaries. If it fails on the first cast, the opponent may re-cast it. If it fails again, the end is declared dead.
Once at rest in a valid position, the jack is centred using the rink centre pins. It then becomes the official target for that end.
The player placing the mat may position it anywhere from minimum to maximum distances from the rear ditch. However, once the first bowl has been delivered, the mat position cannot change for that end.
Before delivery, a player must have at least part of one foot on the mat. At the moment of delivery, at least part of one foot must be on or above the mat. Violation is a foot fault.
On first observation, the umpire warns the player in the presence of the skip. On each subsequent occasion, the bowl is stopped and declared dead. Repeated foot faults are a serious offence.
A player may use forehand or backhand. The bowl must be rolled along the green — not thrown, pitched, or bounced. Delivery cradles are permitted for accessibility purposes.
If a player delivers out of turn, the opposing skip may allow the bowl to remain, or request it be declared dead and returned. The correct player then delivers.
When playing a drive (high-speed delivery), the bowler must clearly warn: "I am firing this bowl." This allows those near the head to move to safety before the bowl is delivered.
A bowl that touches the jack during its original course on the green — or before the next bowl is delivered — is a toucher. Touchers remain in play even if they subsequently enter the ditch within the rink boundaries.
A toucher must be marked with chalk or a coloured disc immediately after it comes to rest. If it isn't marked before the next bowl is delivered, it cannot be claimed as a toucher.
A marked toucher in the ditch remains in play throughout the end. It can still score if it is closer to the jack than the opponent's nearest bowl — even if the jack itself is also in the ditch.
A bowl is dead if it: enters the ditch (unless a toucher), passes outside the rink boundary, rests on the bank, or is delivered in breach of delivery laws.
Dead bowls must be removed from the green promptly and placed in the ditch or collection area. They have no further effect on play and cannot be knocked back into play.
A bowl that passes outside a side boundary and re-enters the rink is dead and must be removed. Some exceptions exist — consult an umpire in cases of doubt.
If the jack is knocked into the ditch within the side boundaries, it remains alive and in play. Players continue to aim at it in the ditch. Bowls that join it in the ditch are dead unless touchers.
The jack becomes dead if it is driven outside a side boundary, over the bank, or cannot be found. A dead jack means the end must be replayed with no score recorded.
If a jack is driven against the bank face and rebounds back onto the rink, it remains alive. If moved by a toucher back onto the rink, it also remains alive.
Once displaced, the jack is played from wherever it comes to rest — even if behind the mat or in the ditch. Bowlers must adjust weight and line accordingly.
Scoring must not begin until all bowls have come to rest, or 30 seconds have elapsed after the skip's request (for bowls at risk of falling). No bowl may be moved until all shots are agreed.
The winning team scores one shot per bowl nearer to the jack than the opponent's nearest bowl. Measurement is between the nearest points of the jack and the bowl.
When it's uncertain which bowl is nearest, a measure is used. If players cannot agree, the umpire adjudicates. Measuring instruments are commonly retractable tapes or telescopic rods.
If the two nearest bowls are equidistant from the jack, no shots are scored. The same team delivers the jack for the next end.
As each shot is agreed, that bowl may be removed. The total must be agreed before moving to the next end. Players must not prematurely move or interfere with the head.
Players at the mat end not delivering must stand at least 1m behind the mat. Players at the head end must stand behind the jack after delivering. No player may walk in a neighbouring rink during play.
No player may deliberately move or interfere with the jack or any bowl in play. Deliberate interference is a serious breach and can result in forfeiture of the match.
No player may delay play by leaving the rink without consent, and then only for a maximum of 10 minutes. If heavy rain forces a stoppage, the head should be left intact. If the green is cleared, that end is declared dead.
No object to assist a player may be placed on the green, bank, or on a bowl or jack. An object may be displayed in the hand as a guide, but only from behind the lie of the jack.
If a bowl in play is accidentally displaced by a player, it must be restored to its original position. If willfully displaced, the opposing skip may have the bowl declared dead or restored.
If the jack or a bowl is disturbed by an outside agency (bird, ball from another rink, spectator), it must be restored. If the original position cannot be determined, the end may be declared dead.
If the jack ends up partially over a side boundary, it is returned and the opponent re-casts it. If it fails to reach the minimum distance, the opponent is entitled to cast it instead.