One of hockey’s most misunderstood and incorrectly cited rules is the American Hockey League’s age restrictions. Per AHL By-Laws, the age limit for eligibility to compete in the league is 18 years or over, on or before September 15 of each season.
So where does the AHL’s oft-cited “20-year-old player rule” come in? This rule is based on the NHL and CHL Agreement, which states a signed player aged 18 or 19 who was claimed from a CHL club and is not retained by the NHL club, must be assigned to the CHL junior club whom he last played for or owes a contractual obligation.
In 1979, the National Hockey lowered the draft eligibility age over a two-year period from 20 to the present-day 18 (with the birthday cut off set at Sept. 15 of the draft’s calendar year). Concurrently, in order to keep CHL teams strong both on the ice and at the box office, CHL players under 20 whose NHL rightsholder deemed not quite ready for the NHL were required to return to their Canadian major junior team rather than playing in the AHL during the season.
Those basic requirements have held in place ever since. However, for young players signed out of Europe or collegiate players who give up their remaining NCAA eligibility in order to sign an NHL entry-level contract or AHL minor league contract, the minimum age to play in the AHL is 18.