| Event: | Women's 400 metre freestyle |
| Competition: | 2018 Pan Pacific Swimming Championships |
| Venue: | Tokyo Tatsumi International Swimming Center |
| Dates: | 11 August (heats &<br>finals) |
| Competitors: | 22 |
| Nations: | 8 |
| Win Value: | 3:58.50 |
| Gold: | Katie Ledecky |
| Goldnoc: | USA |
| Silver: | Ariarne Titmus |
| Silvernoc: | AUS |
| Bronze: | Leah Smith |
| Bronzenoc: | USA |
| Prev: | 2014 |
| Next: | 2022 |
The women's 400 metre freestyle competition at the 2018 Pan Pacific Swimming Championships took place on August 11 at the Tokyo Tatsumi International Swimming Center.[1] The defending champion was Katie Ledecky of the United States.[2]
Prior to this competition, the existing world and Pan Pacific records were as follows:
| World record | 3:56.46 | Rio de Janeiro, Brazil | 7 August 2016 | ||
| Pan Pacific Championships record | 3:58.37 | Gold Coast, Australia | 23 August 2014 |
All times are in minutes and seconds.
| KEY: | bgcolor=ccffcc align=center | QA | Qualified A Final | bgcolor=ddffdd align=center | QB | Qualified B Final | CR | Championships record | NR | National record | PB | Personal best | SB | Seasonal best |
The first round was held on 11 August from 10:00.[3]
Only two swimmers from each country may advance to the A or B final. If a country not qualify any swimmer to the A final, that same country may qualify up to three swimmers to the B final.[4]
| Rank | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|
| 1 | 4:02.57 | QA | |||
| 2 | 4:04.91 | QA | |||
| 3 | 4:06.47 | QA | |||
| 4 | 4:08.72 | QB | |||
| 5 | Madeleine Gough | 4:09.09 | QA | ||
| 6 | 4:10.07 | QB | |||
| 7 | 4:10.58 | QA | |||
| 8 | 4:10.78 | QA | |||
| 9 | 4:11.09 | QB | |||
| 10 | 4:13.00 | QA | |||
| 11 | 4:13.14 | QA | |||
| 12 | Allison Schmitt | 4:13.52 | |||
| 13 | Mikkayla Sheridan | 4:13.74 | QB | ||
| 14 | 4:14.68 | ||||
| 15 | 4:15.30 | QB | |||
| 16 | Mackenzie Padington | 4:16.27 | QB | ||
| 17 | 4:18.80 | QB | |||
| 18 | Nicole Oliva | 4:21.80 | QB | ||
| 19 | Rosalee Santa Ana | 4:29.13 | |||
| 20 | Gianna Garcia | 4:50.44 | |||
| 21 | Osisang Chilton | 5:04.43 | |||
| 22 | Mineri Gomez | 5:14.32 |
The B final was held on 11 August from 18:00.[5]
| Rank | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|
| 9 | 4:08.46 | ||||
| 10 | 4:09.08 | ||||
| 11 | 4:11.09 | ||||
| 12 | Mikkayla Sheridan | 4:11.94 | |||
| 13 | 4:12.43 | ||||
| 14 | Mackenzie Padington | 4:13.97 | |||
| 15 | Nicole Oliva | 4:16.32 | |||
| 16 | Yukimi Moriyama | 4:19.00 |
The A final was held on 11 August from 18:00.[6]
| Rank | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|
| 3:58.50 | |||||
| 3:59.66 | OC | ||||
| 4:04.23 | |||||
| 4 | 4:08.42 | ||||
| 5 | 4:08.81 | ||||
| 6 | 4:09.04 | ||||
| 7 | 4:11.96 | ||||
| 8 | 4:13.25 |