| | Final |  | time |  | gap | L |  | 1. |  Australia | 3:21.18 | GR |  | 4 | 1. |  |  | William Yang 48.80s, Kyle Chalmers 47.55s, Mollie O'Callaghan 52.62s, Emma McKeon 52.21s |  | 2. |  England | 3:22.45 |  | +1.27s | 5 | 2. |  |  | Lewis Burras 48.28s, Tom Dean 48.12s, Anna Hopkin 53.27s, Freya Anderson 52.78s |  | 3. |  Canada | 3:24.86 |  | +3.68s | 3 | 3. |  |  | Javier Acevedo 49.05s, Joshua Liendo 47.89s, Rebecca Smith 54.41s, Maggie Mac Neil 53.51s |  | 4. |  Wales | 3:26.58 |  | +5.40s | 6 | 4. |  |  | Dan Jones 49.41s, Matt Richards 47.51s, Medi Harris 54.33s, Rebecca Sutton 55.33s |  | 5. |  Scotland | 3:30.71 |  | +9.53s | 2 | 5. |  |  | Stephen Milne 50.61s, Evan Jones 49.64s, Emma Russell 55.22s, Evie Davis 55.24s |  | 6. |  Singapore | 3:31.90 |  | +10.72s | 7 | 6. |  |  | Jonathan Tan 49.96s, Quah Zheng Wen 48.80s, Quah Ting Wen 56.40s, Quah Jing Wen 56.74s |  | 7. |  Jersey | 3:42.21 |  | +21.03s | 1 | 7. |  |  | Ollie Brehaut 52.50s, Jack Allan 54.08s, Gemma Atherley 57.61s, Lily Scott 58.02s |  | 8. |  Kenya | 3:43.33 |  | +22.15s | 8 | 8. |  |  | Ridhwan Mohamed 52.75s, Monyo Maina 53.30s, Emily Muteti 57.70s, Imara Thorpe 59.58s | 
 | 91 Competitors from 19 Nations. |  | World and Commonwealth Record : Australia (Jack Cartwright, Kyle Chalmers, Madison Wilson, Mollie O'Callaghan) 3:19.38 Budapest, Hungary 24 June 2022 | 
 |
 | Heats - Friday, 29th July |  | Best 8 times advanced to Final. | 
 | Heat 3 |  | time |  | gap | L | Rk. |  | 1. |  Australia | 3:22.14 | Q, GR |  | 4 | 1. |  |  | Flynn Southam 49.21s, Zac Incerti 48.02s, Meg Harris 52.59s, Madison Wilson 52.32s |  | 2. |  Canada | 3:28.20 | Q | +6.06s | 5 | 3. |  |  | Ruslan Gaziev 48.90s, Stephen Calkins 48.80s, Ella Jansen 55.47s, Mary-Sophie Harvey 55.03s |  | 2. |  Jersey | 3:42.92 | Q | +20.78s | 6 | 7. |  |  | Ollie Brehaut 53.00s, Jack Allan 53.80s, Gemma Atherley 57.72s, Lily Scott 58.40s |  | 4. |  Isle of Man | 3:48.45 | R | +26.31s | 2 | 10. |  |  | Harry Robinson 52.60s, Alex Bregazzi 51.81s, Kiera Prentice 1:03.32, Emma Hodgson 1:00.72 |  | 5. |  Fiji | 3:49.95 |  | +27.81s | 1 | 12. |  |  | David Young 52.20s, Cheyenne Rova 1:03.72s Rosemarie Rova 1:02.35, Hansel McCaig 51.68s |  | 6. |  Seychelles | 3:54.21 |  | +32.07s | 7 | 16. |  |  | Therese Soukup 1:03.96, Aaliyah Palestrini 1:02.43, Simon Bachmann 54.46s, Adam Moncherry 53.36s |  | 7. |  Maldives | 4:14.91 |  | +52.77s | 8 | 17. |  |  | Hamna Ahmed 1:10.93, Mubal Azzam Ibrahim 57.09s, Aishath Sausan 1:10.60, Mohamed Aan Hussain 56.29s |  | -. |  South Africa | DSQ |  |  | 3 | -. |  |  | Clayton Jimmie 50.03s, Guy Brooks, Emma Chelius, Olivia Nel | 
 | Heat 2 |  | time |  | gap | L | Rk. |  | 1. |  England | 3:28.03 | Q | +5.89s | 4 | 2. |  |  | Edward Mildred 48.99s, Jacob Whittle 48.92s, Isabella Hindley 55.76s, Abbie Wood 54.36s |  | 2. |  Wales | 3:29.66 | Q | +7.52s | 5 | 4. |  |  | Dan Jones 49.29s, Calum Jarvis 48.96s, Rebecca Sutton 55.75s, Medi Harris 55.66s |  | 3. |  Scotland | 3:31.09 | Q | +8.95s | 3 | 5. |  |  | Stephen Milne 50.60s, Evan Jones 49.61s, Emma Russell 55.45s, Evie Davis 55.43s |  | 4. |  Guernsey | 3:48.97 |  | +26.83s | 2 | 11. |  |  | Tatiana Tostevin 59.70s, Jonathan Beck 54.16s, Orla Rabey 58.76s, Ronny Hallett 56.35s |  | 5. |  Uganda | 3:51.75 |  | +29.61s | 7 | 13. |  |  | Atuhaire Ambala 55.64s, Tendo Mukalazi 53.10s, Kirabo Namutebi 1:00.14, Avice Meya 1:02.87 |  | 6. |  Barbados | 3:52.46 |  | +30.32s | 6 | 14. |  |  | Jack Kirby 52.24s, Luis Sebastian Weekes 58.54s, Danielle Treasure 1:00.02, Adara Stoddard 1:01.66 |  | 7. |  Samoa | 3:52.67 |  | +30.53s | 8 | 15. |  |  | Brandon Schuster 54.62s, Kokoro Frost 56.82s, Olivia Borg 59.22s, Lushavel Stickland 1:02.01 |  | 8. |  Saint Helena | 4:20.58 |  | +58.44s | 2 | 18. |  |  | William Caswell 1:01.86, Stefan Thomas 57.85s, Vivienne Ponsford 1:11.20, Poppy Davis-Coyle 1:09.67 | 
 | Heat 1 |  | time |  | gap | L | Rk. |  | 1. |  Singapore | 3:33.71 | Q | +11.57s | 5 | 6. |  |  | Darren Chua 50.97s, Jonathan Tan 49.81s, Quah Jing Wen 56.44s, Amanda Lim 56.49s |  | 3. |  Kenya | 3:45.36 | Q | +23.22s | 3 | 8. |  |  | Ridhwan Mohamed 53.23s, Monyo Maina 54.06s, Emily Muteti 58.33s, Imara Thorpe 59.74s |  | 3. |  Bahamas | 3:47.16 | R | +25.02s | 4 | 9. |  |  | Lamar Taylor 52.09s, Davante Carey 53.20s, Zaylie-Elizabeth Thompson 59.94s, Lillian Higgs 1:01.93 | 
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