Erika Fairweather became New Zealand's first gold medallist at a World Aquatics Championships when she was crowned world champion in the Women's 400m freestyle in 2024. It was a monumental competition for the then-20-year-old, who also picked up silver and bronze in the 200m and 800m freestyle events. 

Fairweather went on to contest all three events at the Paris 2024 Olympic Games, in addition to the 4x200m freestyle relay. Progressing through to finals in all four races, Fairweather earned a best finish of fourth place in the 400m freestyle, narrowly missing out on the bronze medal against some of the biggest names in the sport.

Twelve months earlier, Fairweather became the fifth woman in history to break the four-minute barrier in the 400m freestyle at the 2023 World Aquatics Championships, where she claimed bronze in the event amongst a star-studded field of athletes. 

Fairweather has represented New Zealand in the pool since age 14, when she made her international debut at the Junior Pan Pacific Championships in Fiji. In the same year, Fairweather was the youngest competitor at the Youth Olympic Games in Buenos Aires.

At age 15, Fairweather made her Aquablack debut at the 2019 FINA World Championships in Gwangju, where she contested two individual events and led off the women's 4x200m freestyle relay to a tenth-place finish. A few weeks later, Fairweather became World Junior Champion at the 2019 World Junior Swimming Championships in Budapest, claiming gold in the 200m freestyle.

Her first Olympic Games were Tokyo 2020, where, at age seventeen, she was a finalist in the 400m freestyle and a semi-finalist in the 200m freestyle. Fairweather broke Lauren Boyle's longstanding New Zealand record in the 400m freestyle to earn her spot in the final.

In 2022, Faiweather competed at the FINA World Aquatics Championships where she was a finalist in the 400m freestyle and the 4x200m freestyle, in addition to being a semi-finalist in the 200m freestyle. She then went on to compete at her first Commonwealth Games in Birmingham, where she placed fourth in the 400m freestyle and fifth in the 200m freestyle.

Fairweather earned her first senior international medals at the 2022 FINA World Swimming Championships (25m), claiming two silvers in the 400m and 800m freestyle events and helping the women's 4x50m and 4x200m freestyle relay to finals appearances.

Fairweather was born and raised in Dunedin and trained under the guidance of Swim Dunedin's Lars Humer for most of her swimming career. In early 2025, she moved to Auckland's North Shore Swimming Club to work with coach Graham Hill.

Senior pinnacle international medal record

World Aquatics Championships – 1 x gold, 1 x silver, 2 x bronze

World Aquatics Swimming Championships (25m) – 2 x silver