International Ice Hockey Federation (IIHF) rules at the Olympics differ from the NHL in a few ways:

• Roster sizes are smaller in Olympic competition than in the NHL
• Fighting is not permitted in Olympic hockey
• Overtime and shootout procedures can differ from the NHL depending on the Olympic round (details below)
• Rink sizes can be larger than in NHL play but games during the 2026 Milan Cortina Games will be played on an NHL-sized rink

The men's tournament will include 12 teams. Each men's team can have a maximum of 25 players: 22 skaters and three goaltenders. The women's tournament will feature 10 teams. Each women's roster can include a maximum of 23 players: 20 skaters and three goaltenders.

For the 2026 Milan Cortina Games, competition will take place at the Milano Santagiulia and the Milano Rho ice hockey arenas. They both house NHL-sized rinks measuring 200 feet long by 85 feet wide.

Typically, Olympic competition takes place on a larger rink measuring 197 feet long by 98.5 feet wide. This is only the third time the Games will be played on an NHL-sized rink. The 2010 and 2022 Olympics were the others.

Offside: A penalty that occurs when a player on the attacking team precedes the puck into the attacking zone. A player is offside when both skates completely are over the leading edge of the blue line involved in the play.

Hooking: A penalty that occurs when a player uses their stick to impede the progress of an opponent. The act is done by pulling or tugging on any part of an opposing player's body or stick. 

Icing: When a player shoots a puck from behind their own red line and it travels untouched past the opposing team's goal line. Play is stopped when an opponent other than the goalie touches the puck.

Icing occurs when a player shoots a puck from behind their own red line and it travels untouched past the opposing team's goal line. Play is stopped when an opponent other than the goalie touches the puck.

For the purpose of this rule, the center red line divides the ice rink into two halves. The point of last contact with the puck by the team in possession is used to determine whether or not icing has occurred. 

If a player shoots, bats or deflects the puck from their own half of the ice beyond the opposing team's goal line, play is stopped and icing is called. Following an icing penalty, the attacking team will have the choice of which end zone dot the face-off will take place.

No icing is called if:

• The puck enters the net for a goal
• The puck passes through the goal crease
• The offensive team is shorthanded at the instant the puck is shot
• The puck touches any part of an opposing player, including the goalkeeper, before crossing the line
• The puck is iced directly from a player participating in a face-off
• Any player from the other team, except the goalkeeper, is able to play the puck before it crosses the goal line

If at the end of three 20-minute periods in a single preliminary round game, the two playing teams are tied, the teams will then play a “sudden death” overtime period of not more than five minutes with the team scoring first declared the winner (same as the NHL regular season rules). A 10-minute overtime period will be played in a semifinal game or quarterfinal game. The overtime period shall be played with each team at a numerical strength of three skaters and one goalie. If neither team has scored at the end of overtime, the game is decided by a shootout.

The shootout will begin with five different players from each team taking alternate shots. The goalkeepers will defend the same goal as in the overtime period. The players of both teams will take the shots alternately until a decisive goal is scored. The remaining shots will not be taken. If the score is still tied after all shots are taken by each team, the procedure shall continue with a “tiebreak shoot-out” using the same or new players.

Fighting is not allowed in Olympic hockey. Players who willingly participate in a fight will be penalized accordingly by the referee and may be ejected from the game. A fight occurs when at least one player punches or attempts to punch an opponent repeatedly or when two players wrestle and make it difficult for the linespersons to intervene and break it up.

Substitutions can occur at any time during play from a team's bench provided that the player(s) leaving the ice are within 1.50m of their bench and are out of the play before the change is made. Line changes can occur prior to the beginning of a period or after a stoppage in play, the visiting team can complete any player substitutions, followed by the home team.