Ice hockey is played by two teams, each with six players on the ice: five skaters and a goaltender. The aim is to shoot a rubber puck into the opponent’s net. In the NHL, games have three 20-minute periods, and regular-season games tied after regulation go to five minutes of three-on-three overtime and then a shootout. The most important rules to understand are offside, which stops attackers from entering the offensive zone ahead of the puck; icing, which stops teams from simply shooting the puck the length of the ice; and penalties, which send players to the penalty box and give the other team a power play. A goal counts only when the whole puck crosses the goal line.
The basics
| Element | Rule (NHL unless noted) |
|---|---|
| Players | Six per side: center, two wingers, two defensemen, one goalie |
| Game length | Three 20-minute periods; shorter at many youth levels |
| Regular-season overtime | 5 minutes of 3-on-3, then a shootout if still tied |
| Playoff overtime | Full 20-minute 5-on-5 sudden-death periods until a goal |
| Faceoffs | Restart play at designated spots |
| Substitutions | Allowed on the fly or at stoppages |
| Rink size (NHL) | About 200 by 85 feet; international rinks are often wider |
Offside
A team is offside when an attacking player crosses the opponent’s blue line into the offensive zone before the puck. In the NHL, the position of the skates determines offside: a player is onside if at least one skate is on or behind the blue line when the puck crosses it. When offside occurs, play stops and a faceoff is held outside the zone. Delayed offside allows play to continue if the defending team has a chance to clear the puck, as long as attacking players leave the zone before touching the puck.
Icing
Icing occurs when a player shoots the puck from their own side of the center red line across the opponent’s goal line without it being touched. Play stops, and the faceoff moves to the offending team’s defensive zone. The team that iced the puck cannot change players before that faceoff. A shorthanded team is allowed to ice the puck without penalty. The NHL uses hybrid icing, in which the linesman judges whether a defender or attacker would reach the puck first, based on who is ahead at the faceoff dots, to reduce dangerous races into the boards.
Penalties
| Penalty | Length and effect |
|---|---|
| Minor | 2 minutes; ends early if the opponent scores |
| Double minor | 4 minutes, served as two minors |
| Major | 5 minutes; does not end early if the opponent scores |
| Misconduct | 10 minutes for the player, but the team is not shorthanded |
| Game misconduct | Player ejected from the game |
| Match penalty | Ejection for serious offenses, often with further review |
Common penalties include tripping, hooking, slashing, holding, interference, high sticking, cross-checking, roughing and boarding. When a penalty is called against a team, the referee raises an arm and waits until the offending team regains control of the puck before blowing the whistle, a situation called a delayed penalty. During this time, the non-offending team often pulls its goalie for an extra attacker.
Scoring goals
A goal is scored when the entire puck crosses the goal line between the posts and under the crossbar. Goals can be disallowed for reasons such as being deliberately kicked in with a distinct kicking motion, batted in with a hand, directed in with a stick above the crossbar, or scored after goaltender interference or offside. In the NHL, video review and coach’s challenges can be used to confirm or overturn certain goals.
The goaltender
The goalie is the only player who can hold the puck with their glove. Goalies wear extra protective equipment and have special rules, such as restrictions on playing the puck behind the net in the NHL, where a trapezoid-shaped area limits where they can handle the puck. Goalies can be penalized, but another player serves the penalty time in the box. Teams can pull their goalie for an extra skater, typically late in a game when trailing or during a delayed penalty.
How a game flows step by step
- Opening faceoff at center ice to start each period.
- Play continues until a goal, offside, icing, penalty, puck out of play or goalie freeze.
- Faceoffs restart play at the appropriate spot.
- Line changes happen on the fly or at stoppages.
- Penalties create power plays and penalty kills.
- Periods end after 20 minutes of play, with intermissions between.
- Overtime or shootouts decide tied games, depending on league and game type.
The rink and its markings
A hockey rink is divided into three zones by two blue lines: the defensive zone, the neutral zone and the offensive zone. The center red line splits the rink in half and is used for icing decisions. Goal lines run across each end, with the goal nets placed on them. Faceoff circles and dots mark where play restarts: one at center ice, four in the neutral zone and two in each end zone. The goal crease, a semicircle in front of each net, is the goalie’s protected area, and players who interfere with the goalie there can have goals disallowed or be penalized. Understanding these markings makes it easier to follow offside, icing and faceoff decisions during a game.
Line changes and bench rules
Hockey allows unlimited substitutions, and teams change lines frequently, often every 40 to 60 seconds, to keep players fresh. Changes can happen on the fly while play continues, but the player leaving the ice must be close to the bench, generally within a few feet, before the replacement steps on. If a team has too many players on the ice and one of them plays the puck or interferes with play, it can be called for a too-many-men bench minor. At stoppages, the home team usually gets the last change in the NHL, allowing its coach to match lines against the visiting team.
Differences between leagues
Rules differ between the NHL, international hockey governed by the IIHF, college leagues and youth associations such as USA Hockey and Hockey Canada. Examples include body checking, which is not allowed in many youth age groups and in women’s hockey, overtime formats, rink dimensions and some icing and goaltender rules. Rules note: this overview is simplified and based mainly on NHL rules; always check the current rulebook for your league for exact details.
Safety rules
Many rules exist to protect players, especially from head injuries. Penalties for checks to the head, checking from behind and boarding aim to reduce dangerous hits. Players must wear helmets, and many leagues require visors, cages, neck guards or mouthguards. Health note: this article is general information, not medical advice. Players with suspected concussions should be removed from play and assessed by a medical professional according to league protocols.
Common misconceptions
- Icing is always called. Shorthanded teams can ice the puck.
- Majors end when a goal is scored. Only minors end early.
- Offside depends on the puck carrier only. Any attacker entering early can cause offside.
- All leagues allow body checking. Many youth and women’s leagues do not.
Frequently asked questions
How long is an NHL hockey game?
Three 20-minute periods of play, plus overtime or a shootout if needed.
What is icing in hockey?
Shooting the puck from your own side of center across the opponent’s goal line untouched, which stops play.
What is a power play?
When one team has more players on the ice because the other team has a player serving a penalty.
