How Many Periods in Hockey?

An NHL hockey game is divided into 3 periods of 20 minutes each, for a total of 60 minutes of playing time. Between each period there is an 18-minute intermission during which the ice is resurfaced by Zamboni machines to restore a smooth skating surface.

Hockey is unique among major sports in using three periods rather than two halves or four quarters. This format dates back to the early 1900s and was adopted primarily for practical reasons: the ice surface deteriorates significantly during 20 minutes of professional play, and resurfacing twice rather than once produces a faster, safer game with better puck movement throughout.

If the game is tied after regulation, the NHL uses a 5-minute sudden-death overtime period played 3-on-3 (instead of the regular 5-on-5). If still tied, a shootout determines the winner. Playoff games skip the shootout and instead play full 20-minute sudden-death overtime periods at 5-on-5 until someone scores, which has produced some of the longest games in professional sports history.

🏒 Period Structure

🧊 Why 3 Periods Instead of 2 Halves?

The three-period format exists because of ice maintenance. After 20 minutes of NHL-level play with players skating at speeds up to 30 mph, the ice surface becomes rutted, snowy and uneven. The two intermissions allow Zamboni machines to lay a fresh sheet of water that freezes into a smooth surface, maintaining the speed and skill that define modern hockey. Without these breaks, the third phase of a game would be played on significantly degraded ice, slowing the pace and increasing injury risk from unpredictable puck bounces.