Boundary count rule was a tiebreaker rule used in cricket to determine the winner of a match in case of a tie. The rule stated that the team that scored more boundaries (fours and sixes) in the match would be declared the winner. However, this rule was scrapped by the International Cricket Council (ICC) after the 2019 World Cup final between England and New Zealand ended in a tie and was decided by the boundary count rule.

The boundary in cricket is the perimeter of the playing field, and it is also the term given to a scoring shot where the ball is hit to, or beyond, that perimeter, which generally earns four or six runs for the batting team). The boundary is the edge of the playing field, or the physical object (often a rope) marking the edge of the field. In low-level matches, a series of plastic cones or flags are sometimes used. Since the early 2000s, the boundaries at professional matches are often a series of padded cushions carrying sponsors logos strung along a rope).

In case of a tie in a cricket match, a Super Over is played, where each team faces six balls, and the team that scores more runs is declared the winner. If the Super Over is also tied, then it is repeated until one team has more runs than the other. In group stages, if the Super Over is tied, the match will be tied. In Semi Finals and Finals, the Super Over will be repeated until one team has more runs than the other.

In conclusion, the boundary count rule was a tiebreaker rule used in cricket to determine the winner of a match in case of a tie. However, it was scrapped by the ICC after the 2019 World Cup final. In case of a tie, a Super Over is played, and if it is also tied, it is repeated until one team has more runs than the other.