Marathon swimming rules rules, for watching
Start with the rules you see all the time, then the ones that change results.
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- What is marathon swimming, and how is it won?
- How does an open water race start?
- What must a swimmer do to stay on the course?
- What do the yellow and red flags mean in open water swimming?
- May a swimmer stand up or hold on to something during the race?
- Can a swimmer draft behind another swimmer or a boat?
- How do swimmers eat and drink during the race?
- How does an open water race finish?
- How is an open water race timed?
- How long may a swimmer take to finish?
- What happens if a race has to be stopped?
- How warm or cold may the water be, and when are wetsuits worn?
- What may an open water swimmer wear and carry?
- How does the open water mixed relay work?
- What is the 3 km knockout sprint?
- Who runs an open water race, and how is a decision challenged?
Where these rules come from
| Tag | Document |
|---|---|
| OWS plus article number | World Aquatics, Competition Regulations, Part Three: Open Water Swimming Rules, in force as from 1 January 2025. Read in full for this set: Articles 1 to 9 (programme, officials and their duties, the start, the race, the finish, swimwear and technology, identification, facilities and timing). Article 10 (water quality) was read as far as the bacterial limits and sampling schedule. Article 11 (safety regulations) and the appendices were not read |
| "Part One" plus article number | The same document, Part One: Article 13 (protests and appeals) |
| "Swimming Rules" plus article number | Part Two in its February 2026 edition, for the comparisons with the pool |
| R | "Why the rule exists", or a point reasoned from the rule, not stated in it |
| C | Common usage or general knowledge, not a rule |
All checked on 14 October 2026. The file is a text PDF with article numbers in the text layer.
The edition is from January 2025. The swimming part of the same regulations has a February 2026 edition, so the open water part has probably been revised as well. The newer text is not saved.
The name. The founder's list says "marathon swimming", which is what the Olympic programme calls the 10 km race. The regulations say "Open Water Swimming" throughout and cover the 5 km, the relay and the knockout sprint as well. This set covers all of them under the founder's folder name.
Not covered: Article 11 (open water safety regulations) and the appendices; the 2026 edition; masters open water swimming; the open water leg of a triathlon; para swimming.
Not covered: Article 11 (open water safety regulations) and the appendices; the 2026 edition; masters open water swimming; the open water leg of a triathlon; para swimming.