What are the basic Canadian field, team and down rules?

• Field: 110 yards (100 metres) long by 65 yards (60 metres) wide, plus an end zone 20 yards (18.28 metres) long at each end. Hash marks are 24 yards (22 metres) from each sideline, and the field is marked every 5 yards (metres).
• Players: 12 on the field at any one time. More than 12 players and/or substitutes on the field during a play is illegal (L10), and coaches, not officials, are responsible for fielding the correct number. The rule book recommends at least 24 players dressed to start a game.
• Downs: after a kick off, the team in possession has 3 attempts (downs) to gain 10 yards (metres). If it gains them, the downs begin again; if not, the ball goes to the opponents as 1st down where the ball became dead.
• Substitutions: substitutes may enter only when the ball is dead, and no substitute may enter once the Down Judge and Line Judge raise their arms after Team A breaks its huddle.
• Registration: all players must be registered by name and number with the scorer before the game.

Source: Canadian Amateur Rule Book for Tackle Football 2026-2027, Rule 1 (Sections 1, 4 and 12), Rule 4 Section 6 Article 1, and Rule Modifications.