AFL

AFL Interchange Rules Explained

By the BenchBalancer Team — 30 April 2026 · 7 min read

If you have stepped onto the boundary line as a community AFL or Auskick coach for the first time, the interchange rules can feel like one of those bits of footy lore that everyone assumes you already know. Most coaches pick it up by osmosis — until a runner from another team asks how many subs you have left and you realise you have not been counting. This guide pulls it all together: what the AFL standard actually says, how community and junior grades adapt it, and how to manage your bench so every kid gets a genuine run.

This is a coach's explainer, not a rulebook. Always check your local league rules before round one — every association tweaks the senior standard for safety, fairness, and player development at junior level.

The Senior AFL Standard in One Paragraph

An AFL team has 18 players on the field, 4 on the interchange bench, and unlimited swaps within a strict rotation cap (currently 75 rotations per match for senior AFL, counted as on-and-off). Each interchange happens through a designated gate, supervised by an interchange steward. The 23rd player slot, formerly known as the substitute or "medical sub", has shifted in and out of the laws over the years — at the time of writing, the AFL allows a medical substitute who can replace an injured player but does not count toward the rotation cap. Community football works similarly but with much more flexibility.

The Bench: Active vs. Reserve

"On the bench" actually covers two distinct states. An interchange player is dressed, ready to come on, and counts toward the active 22 (or 21 in junior grades). A reserve sits out the whole match — common in junior squads of 25-plus players where rosters rotate week to week. Coaches need a system for both. We recommend a visible bench list with clock time on and off, plus a separate "out today" list for the parents who ask.

Pre-match, set a fairness target the same way basketball coaches do. Total minutes on the field divided by squad size, multiplied by 18 (or whatever your grade plays), tells you average minutes per player. For a 60-minute community match with a 22-player squad, that is roughly 49 minutes each — which means an active player is on the field about 80% of the time, with the rest spent on the interchange bench.

Junior Grades: How Community Football Adapts the Rules

Auskick and junior AFL are the most modified versions of the game. AFL Australia's NAB AFL Auskick program runs four-versus-four through to nine-versus-nine modified formats, with no scoreboards and no ladders for the youngest age groups. Interchange in these formats is essentially a coach-controlled rotation — kids cycle on and off in roughly equal blocks, regardless of position.

Once you hit Under-12s and above, most state leagues adopt formats closer to senior AFL: 15-a-side or 18-a-side, quarters of 12 to 20 minutes, and bench rotations supervised informally by a runner. The big difference from senior football is that almost every junior league mandates equal time. AFL Victoria, for example, requires that every player listed on the team sheet plays at least half the available game time at younger ages. That makes coach-managed rotation a compliance issue, not just a fairness one.

The Blood Rule and Concussion Subs

If a player is bleeding, they must come off the field until the bleeding has stopped and any blood-stained kit has been changed. This is a "blood rule" interchange and does not count toward your rotation cap at senior level. At community level, a blood-rule swap is informal — get the kid off, sort out the cut, and have someone else cover the position.

Concussion is treated more strictly. AFL protocols (community and senior) require any player suspected of concussion to be removed from play immediately and not returned without medical clearance. As a coach, this is one of the rare cases where a substitution is not optional — the player is out for the day, full stop. Plan your rotation knowing one or two of your interchange spots may need to absorb the loss without warning.

Rotation Strategy for Community and Junior Coaches

Senior AFL coaches obsess over rotation efficiency because too many subs disrupts midfield structure and too few burns out runners. At community and junior level the calculus is different — you are juggling fairness, fitness, and learning. Three rules of thumb make the maths manageable:

• Plan rotations in line blocks, not individual swaps. Send three or four players off together at a quarter break, bring three or four on. It is easier to track and easier to coach.
• Match stint lengths to age. Under-9s should not be on the field for more than six or seven minutes without a breather. Under-15s can comfortably do 12 to 15 minutes between rotations.
• Use the runner. A good runner is your interchange auditor — they know who has been on the longest, who looks tired, and who is sulking on the bench because they have not touched the ball.

How BenchBalancer Handles AFL Rotations

Tracking 22 players, 18 on-field positions, four quarters, and an equal-time mandate is exactly the kind of admin coaches do not need to do by hand. BenchBalancer's AFL rotation manager uses a line-based interchange model — the algorithm groups players into sub-able lines, calculates target minutes per player, and tells you who to swap on and off at every break and during play. When a kid is unavailable due to a blood-rule break or a concussion sub, our AFL game engine redistributes their unused minutes across the rest of the squad in real time. The runner gets a notification, you nod from the bench, and the rotation balance holds.

For a quick walkthrough of how the algorithm works across all four sports, head to the BenchBalancer homepage.