How many replacements may we name?

• Club and other non-international matches: the match organiser (your provincial union or competition) decides how many replacements may be nominated, up to a maximum of eight (Law 3.5).
• International matches: a union may nominate up to eight (Law 3.4).
• No more than 15 players may be on the playing area during play (Law 3.1), though a match organiser may authorise matches with fewer per side (Law 3.2).
• If a team has too many players, the opposition may object; the referee orders the captain to reduce the number and awards a penalty. The score at that moment stands (Law 3.3).
• Where the match organiser allows rolling replacements, interchanges are capped at 12 (Law 3.34).

Make sure your bench meets the front-row minimum for your squad size (Law 3.8).