Swimming at the 2025 World Aquatics Championships – Women's 200 metre butterfly

Summer McIntosh of Canada entered the event as the favorite, aiming for her fourth consecutive major title. She had set a new Canadian, Commonwealth, and Americas record of 2:02.26 at the Canadian Trials, the second-fastest time in history and 0.45 seconds shy of Liu Zige’s 2009 world record of 2:01.81. Given that McIntosh swam her best time each of the previous three summers in the major final, she was predicted to be well-positioned for a potential world record challenge. Regan Smith of the United States, a consistent medalist since 2021, ranked second this year with a time of 2:05.38 and was the only other swimmer in the field with a personal best under 2:04. Her teammate Caroline Bricker had a breakout year, clocking 2:05.80 to win U.S. Nationals and ranking third globally in 2025. Also under 2:07 this season were Brittany Castelluzzo of Australia (2:06.86) and Keanna Macinnes of Great Britain (2:06.93), both of whom were predicted to contend for bronze. China's 12-year-old Yu Zidi swam 2:06.83 at Chinese nationals and was predicted to potentially reach the final. Other final hopefuls included Helena Rosendahl Bach of Denmark, Emily Richards of Great Britain, Lillou Ressencourt of France, and Ma Yonghui of China. ==Qualification==

Each National Federation was permitted to enter a maximum of two qualified athletes in each individual event, but they could do so only if both of them had attained the "A" standard qualification time. For this event, the "A" standard qualification time was 2:09.21 seconds. Federations could enter one athlete into the event if they met the "B" standard qualification time. For this event, the "B" standard qualification time was 2:13.73 seconds. Athletes could also enter the event if they had met an "A" or "B" standard in a different event and their Federation had not entered anyone else. Additional considerations applied to Federations who had few swimmers enter through the standard qualification times. Federations in this category could at least enter two men and two women to the competition, all of whom could enter into up to two events. ==Records==

Prior to the competition, the existing world and championship records were as follows. The following new records were set during this competition. ==Heats==

The heats took place on 30 July at 11:21. ==Semifinals==

The semifinals took place on 30 July at 20:16. ==Final==

The final took place on 31 July at 14:02. == Notes ==