Seeding, Lane Assignments, Swim-Offs & Order of Heats

[SwimGPT]

TL;DR
• Prelims & timed finals are seeded by entry times. Ties on entry times → draw.
• Inside a heat, lanes go center-out (fastest in the middle).
• 2-, 3-, and 4+ heat patterns determine which swimmers land in which heat.
• Swim-offs break ties for finals spots (unless all parties agree otherwise). Max 45 min to run it.
• Finals lanes: fastest in middle, then alternate sides. Alternates can fill scratches without full reseed.

How Prelims Seeding Works

• Swimmers are listed by submitted entry time, fastest to slowest.
• Identical times → order decided by draw.
• No time → seeded last, by draw.
• Lanes within each heat use the same center-out pattern as finals.

Heat patterns (when finals are scheduled):

• One heat → everyone swims that heat in prelims; finals still run as scheduled.
• Two heats → “snake” order: fastest → Heat 2, next → Heat 1, next → Heat 2, etc.
• Three heats (not distance events) → H3, H2, H1, then repeat.
• Four or more heats (not distance events) → the fastest three heats follow the 3-heat pattern; earlier heats get the rest.
• Distance events (400/500, 800/1000, 1500/1650) → the fastest two heats use the 2-heat snake pattern.

🐢 When there are 2+ heats, at least three swimmers must be seeded into each prelim heat. Scratches can drop it below three.

Lane Assignments (Center-Out)

Lanes are assigned fastest in the center, then alternating sides outward.

8-lane example:

Order →   1st  2nd  3rd  4th  5th  6th  7th  8th
Lane  →    4    5    3    6    2    7    1    8

Other pool sizes:

• 6 lanes → 3, 4, 2, 5, 1, 6
• 10 lanes → 5, 6, 4, 7, 3, 8, 2, 9, 1, 10

Quick Visuals: Which Heat Do I Land In?

Two heats:

Rank:   1   2   3   4   5   6   7   8 ...
Heat:   2   1   2   1   2   1   2   1 ...

Three heats:

Rank:   1   2   3   4   5   6   7   8   9 ...
Heat:   3   2   1   3   2   1   3   2   1 ...

Four+ heats:
The last three heats follow the 3-heat pattern. Earlier heats fill with remaining swimmers.

Distance events:
The last two heats follow the 2-heat snake.

Swim-Offs

• Swim-offs decide advancement when swimmers tie for a finals spot.
• Can be replaced by another method (e.g., coin toss) if all agree.
• Must be swum within 45 minutes after the last heat of any event that session where a tied swimmer competed.
• Judged the same as the original race.
• DQ in a swim-off → swimmer is placed in the lowest position being contested (still eligible as an alternate).
• Times from prelims, not swim-offs, are used for finals seeding.

Finals Seeding

Finals lanes are assigned by prelim times only. Ties for lane spots → draw.

• 6 lanes → 3, 4, 2, 5, 1, 6
• 8 lanes → 4, 5, 3, 6, 2, 7, 1, 8
• 10 lanes → 5, 6, 4, 7, 3, 8, 2, 9, 1, 10

Timed Finals

• Last heat = fastest swimmers, earlier heats = slower swimmers.
• Center-out lane assignment.
• First heat must have at least three swimmers/relays.
• Places awarded on times only; ties remain ties.

Order of Heats

• Prelims/timed finals → normally slowest to fastest, but meet may choose fastest-first. Women’s and men’s heats may alternate.
• Finals → may be A–B–C or reversed (A before B/C).
• Always check the meet announcement.

Alternates

• If someone scratches finals, athletes may move up, and alternates can be used to fill the slowest heat.
• In non-scoring heats (no points/awards), alternates can be added to any empty lane.

Real-Life Example

You’re 12th seed in an 8-lane, 100 free with 3 prelim heats (not a distance event).

Seeding goes:
1→H3, 2→H2, 3→H1, 4→H3, 5→H2, 6→H1, 7→H3, 8→H2, 9→H1, 10→H3, 11→H2, 12→H1.

Heat 1 (seeds 3, 6, 9, 12) gets lanes:

• 3 → Lane 4
• 6 → Lane 5
• 9 → Lane 3
• 12 → Lane 6

Quick Tips

• 🕒 Be ready for a swim-off within 45 minutes if you tie for a finals spot.
• 🏊 Always read the meet announcement — it may change order of heats.
• 🎲 Tied entry times are broken by draw, not swim-off.

📖 Official reference: USA Swimming Rulebook (2025), §102.5 Seeding, Lane Assignments, Swim-Offs, and Order of Heats