| Event: | Women's 100 metre backstroke |
| Competition: | 2021 FINA World Swimming Championships (25 m) |
| Venue: | Etihad Arena |
| Location: | Abu Dhabi, United Arab Emirates |
| Dates: | 16 December (heats and semifinals) 17 December (final) |
| Competitors: | 49 |
| Nations: | 43 |
| Win Value: | 55.20 |
| Gold: | Louise Hansson |
| Goldnoc: | SWE |
| Silver: | Kylie Masse |
| Silvernoc: | CAN |
| Bronze: | Katharine Berkoff |
| Bronzenoc: | USA |
| Prev: | 2018 |
| Next: | 2022 |
The Women's 100 metre backstroke competition of the 2021 FINA World Swimming Championships (25 m) was held on 16 and 17 December 2021.[1]
Prior to the competition, the existing world and championship records were as follows.
The heats were started on 16 December at 11:51.[2]
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
|---|---|---|---|---|---|---|
| 1 | 4 | 7 | 55.92 | Q | ||
| 2 | 5 | 4 | 55.95 | Q | ||
| 3 | 4 | 4 | 56.12 | Q | ||
| 4 | 5 | 5 | 56.41 | Q | ||
| 5 | 5 | 7 | 56.76 | Q | ||
| 6 | 4 | 3 | 57.06 | Q | ||
| 7 | 3 | 3 | 57.07 | Q | ||
| 8 | 3 | 4 | 57.09 | Q | ||
| 9 | 3 | 1 | 57.36 | Q | ||
| 10 | 4 | 5 | 57.42 | Q | ||
| 11 | 5 | 0 | 57.72 | Q | ||
| 12 | 3 | 7 | 57.82 | Q | ||
| 13 | 4 | 6 | 58.05 | Q | ||
| 14 | 3 | 6 | 58.33 | Q | ||
| 15 | 4 | 1 | 58.39 | Q | ||
| 16 | 1 | 7 | 58.43 | Q, NR | ||
| 17 | 5 | 3 | 58.46 | |||
| 18 | 4 | 2 | 58.54 | |||
| 19 | 3 | 5 | 58.63 | |||
| 20 | 5 | 2 | 59.15 | |||
| 21 | 5 | 6 | 59.36 | |||
| 22 | 3 | 8 | 59.58 | |||
| 23 | 5 | 8 | 59.64 | |||
| 24 | 4 | 0 | 59.76 | |||
| 25 | 3 | 2 | 59.87 | |||
| 26 | 4 | 8 | 59.94 | |||
| 27 | 5 | 9 | ||||
| 28 | 5 | 1 | ||||
| 29 | 3 | 9 | NR | |||
| 30 | 2 | 4 | NR | |||
| 31 | 2 | 5 | NR | |||
| 32 | 2 | 6 | ||||
| 33 | 3 | 0 | ||||
| 34 | 2 | 3 | ||||
| 35 | 2 | 8 | NR | |||
| 36 | 1 | 8 | ||||
| 37 | 2 | 1 | ||||
| 38 | 1 | 1 | ||||
| 39 | 2 | 0 | ||||
| 40 | 1 | 3 | ||||
| 41 | 1 | 2 | ||||
| 42 | 1 | 4 | ||||
| 43 | 2 | 7 | ||||
| 44 | 2 | 9 | ||||
| 45 | 1 | 9 | ||||
| 46 | 1 | 5 | ||||
| 47 | 1 | 0 | ||||
| 48 | 1 | 6 | ||||
| 2 | 2 | |||||
| 4 | 9 |
The semifinals were started on 16 December at 19:16.[3]
| Rank | Heat | Lane | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 5 | 55.85 | Q, NR | |||
| 2 | 1 | 4 | 56.05 | Q | |||
| 2 | 2 | 3 | 56.05 | Q | |||
| 4 | 2 | 5 | 56.07 | Q | |||
| 5 | 2 | 4 | 56.10 | Q | |||
| 6 | 2 | 6 | 56.65 | Q, NR | |||
| 7 | 1 | 6 | 56.72 | Q | |||
| 8 | 1 | 3 | 57.26 | Q | |||
| 9 | 2 | 7 | 57.36 | ||||
| 10 | 1 | 1 | 57.45 | NR | |||
| 10 | 2 | 2 | 57.45 | ||||
| 12 | 1 | 2 | 57.59 | ||||
| 13 | 1 | 7 | 57.62 | ||||
| 14 | 2 | 1 | 57.91 | ||||
| 15 | 1 | 8 | 58.13 | ||||
| 16 | 2 | 8 | 59.46 |
The final was held on 17 December at 19:35.[4]
| Rank | Lane | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|
| 4 | 55.20 | NR | ||||
| 6 | 55.22 | NR | ||||
| 2 | 55.40 | |||||
| 4 | 5 | 55.53 | ||||
| 5 | 3 | 55.87 | ||||
| 6 | 1 | 56.11 | ||||
| 7 | 8 | 56.68 | ||||
| 8 | 7 | 56.99 |