Teams have four different "roster" limits to balance under the league’s regulations; a 20-player "dressed list" for games, a 23-player active NHL roster, a 50-contract maximum, and a 90-player maximum reserve list.
Starting with the largest and working our way down, teams are only allowed to have up to 90 players on its reserve list, whether signed to a standard player contract (SPC) or unsigned. From there teams are only allowed to have up to 50 players signed to contracts for any given season, including those for the players on the active roster and injured reserve lists. The unsigned players are draft picks of the club who have not yet been signed. In most cases, an organization retains an unsigned drafted player’s rights for two seasons after his drafted year, with some extended timeframes provided for US College players and for European players, among others, but that’s for another topic later on.
Every player on the 23-person active NHL roster, plus any player on the injured reserve list, must be under contract (and count toward the 50 contract maximum) and every team must have at least 24 players and three goaltenders under an SPC. Beyond those parameters, a team has wide latitude to make up its 50 contracts. In actuality, most teams opt not to use the full 50-contract maximum to give the organization the flexibility to make roster moves – trades, waiver claims, or player signings – at any given time. Most teams carry a significant number of signed players at the minor professional level, AHL being the highest minor pro league in North America. Since these players are already signed to contracts, it’s easy for clubs to recall the player(s) to the NHL as needed.
Other players may be signed to contracts but returned to the player’s junior club – most often this takes place between an NHL club and Canadian Major Junior teams (teams that play in the Ontario Hockey League, Quebec Major Junior Hockey League, or Western Hockey League, collectively the CHL). But 18 and 19-year-old players assigned to their team in the CHL do not count against the 50-contract maximum, until they have played at least 11 NHL games in one season.
The 50-contract limit has an interesting distinction in that the limit pertains to the season(s) for which a contract is valid. All NHL player contracts expire on June 30. The year varies from contract to contract, but the day remains the same (as we’ll discuss more when we look at player contracts in later editions of the feature). Knowing it has expiring contracts coming off its 50-contract maximum, a team can sign players to contracts for the following season. By doing so a team may have more than 50 different players signed to valid SPCs, as long as 50 or fewer are signed to valid SPCs for that current season AND fewer than 50 SPCs on tap for the upcoming season.
The 23-man roster limit is in place from the conclusion of the preseason until 12:01 am on the day of the NHL’s Trade Deadline. After that teams are allowed to have an unlimited active roster at the NHL level, provided players are signed to one of their 50 contract slots. NHL teams are only allowed to dress a maximum of 20 players – 18 skaters and two goaltenders – for any given game, but those 20 must come from the 23-player active roster.
Both the 23-player active roster and 20-player game roster can change day-to-day and game-to-game. All changes to the team’s 23-player active roster must be cleared through the NHL’s Central Registry before the move is considered finalized (and before the player is eligible to play in a game). In most cases the clearance from Central Registry is simple and completed in a nominal time span. Changes to the 20 players on the game roster are even easier – the list is submitted to the NHL official (either referee or official scorer) by the team (usually the head coach) moments before the start of the game. Prior to submitting the list, the team can choose from any members of its 23-man active roster.
As for the 20-player game roster, according to Rule 5.2, "Only players and goalkeepers on the list submitted to the Official Scorer before the game may participate in the game." The rule further states that any goals scored while ineligible players are on the ice are subject to be disallowed – at the time of the goal – and the ineligible player(s) removed from the game with the offending team not allowed to replace the ineligible player’s roster spot. However, the rule continues, "No additional penalties are to be assessed but a report of the incident must be submitted to the Commissioner."
There is an exemption to the rule should both of the goaltenders on the game roster become "incapacitated" but that is an extremely specific rule that has very rarely come into play in the league’s long history.