Basic Overtime Format
In NHL playoff games, if the score is tied after 60 minutes of regular play, the game goes to overtime. The first overtime period is 20 minutes long and uses a 3-on-3 format instead of the normal 5-on-5. This reduced number of players creates more scoring chances and is designed to end the game more quickly.
Sudden-Death Rules
Overtime in the playoffs is sudden-death, meaning the game ends immediately when one team scores a goal. There is no requirement to play out the full 20-minute overtime period. As soon as the puck goes into the net, that team wins the game and the series continues or ends based on the match situation.
Multiple Overtime Periods
If the game remains tied after the first overtime period ends with no goals scored, additional 20-minute overtime periods are played. The second overtime period and any periods after that return to a full 5-on-5 skater format. This continues until one team scores and wins the game.
Why 3-on-3 Overtime
The NHL introduced 3-on-3 overtime in the regular season in 2015, and it has also been used in playoffs. This format was created to increase scoring chances by reducing the number of players on the ice and opening up more space. It encourages teams to play offensively rather than defensively, leading to faster-paced hockey.
Playoff Implications
Playoff overtime is critical because the winner of a playoff game advances toward winning their series. There is no tiebreaker or points system in the playoffs like in the regular season. Every playoff game must have a winner, so overtime periods continue indefinitely until a goal is scored. 
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