Gilmour was born in Dunedin in 1979. Both her father and maternal grandfather were mechanics, grounding her in automotive culture from an early age. She completed a design studies degree at the University of Otago and, outside of racing, operates a Suzuki car dealership in Dunedin.
Gilmour built her early reputation in the New Zealand Rally Championship, where she finished as runner-up on three separate occasions. The championship produced some of New Zealand's most respected rally talent, and Gilmour's consistent top-two finishes established her as one of the country's leading rally drivers.
In 2014, Gilmour broke new ground by becoming the first woman to enter the Global Rallycross Championship. She competed under Rhys Millen Racing in a Hyundai Veloster Turbo, demonstrating her ability to adapt from traditional rally stages to the short, high-intensity format of rallycross.
When the Extreme E electric off-road racing series launched in 2021, Gilmour joined Veloce Racing as reserve driver for the inaugural season. She stepped in to replace regular driver Jamie Chadwick at two events, gaining her first competitive experience in the all-electric SUV format.
Gilmour joined McLaren XE for the 2022 Extreme E season in what became the most significant chapter of her career. In doing so, she became the first female factory driver to race for McLaren in any motorsport discipline. Paired with Tanner Foust, she delivered a podium finish at the season-ending Energy X-Prix, making her the first woman to stand on a podium representing McLaren.
Both Gilmour and Foust were retained for the 2023 season. The pairing secured another podium, finishing second in Round 4 at the Hydro X-Prix. However, the season was disrupted when Gilmour suffered a fractured rib and a concussion following a crash during the first free practice session at Round 7, the Island X-Prix II. She was ruled out for that round and the next, with championship reserve driver Tamara Molinaro stepping in. For the final two rounds, McLaren announced Gilmour was still recovering from her injuries and brought in JBXE driver Hedda Hosås as a replacement.
At the end of the 2023 season, McLaren announced that both Gilmour and Foust would depart the team after two seasons together.
Emma Gilmour's career represents a series of firsts for women in motorsport. Her transition from domestic rally championships in New Zealand to the international stage of Extreme E, and ultimately to a factory seat with one of the most storied names in motorsport, charts a path that few drivers — male or female — have matched across such varied disciplines. Her three runner-up titles in the New Zealand Rally Championship and her landmark achievements with McLaren place her among the most significant women in Australasian motorsport history.