Having started his racing career in karts, Horner’s career in car racing started after he won a Formula Renault scholarship in 1991. He competed in the 1992 British Formula Renault Championship with Manor Motorsport, finishing that season as a race winner and the highest placed rookie. He then moved up to British Formula Three for 1993, finishing second in the Class B Championship for P1 Motorsport and winning five races before moving to the Fortec and ADR teams in 1994 and 1995, and then to the TOM’S team in 1996. In 1996 he also raced in British Formula Two.

Horner moved up to Formula 3000 in 1997, founding the Arden team. According to Horner he set the team up with borrowed money, including a loan from his father, and persuaded P1 Motorsport founder Roly Vincini to take on the role of his race engineer. He bought a second-hand trailer for the team from Helmut Marko, who as head of the Red Bull Junior Team was one of Horner’s main rivals as a manager in F3000, and who he would later work closely with at Red Bull.

Arden also competed in Italian F3000 in 2000 winning three races and finishing second in the Championship with Warren Hughes.

Wirdheim stayed in 2003, with Enge replaced by Townsend Bell. Björn Wirdheim won the title by a 35-point margin to second-placed Ricardo Sperafico. Arden retained the Team Championship.

At this point Horner was looking for an opportunity to move into Formula One. After discussions with Eddie Jordan regarding buying Jordan Grand Prix came to nothing due to disagreements over costs, in November 2004 the Austrian energy drink company, Red Bull, purchased Jaguar F1 Team, which became Red Bull Racing. In January 2005, Horner was appointed to head the team, becoming the youngest team principal at the time. Despite being appointed only eight weeks before the season-opening Australian Grand Prix, the team got off to a good start under his stewardship, with drivers David Coulthard and Christian Klien finishing fourth and seventh in Australia, and they went on to score a total of 34 points for the team compared to the nine taken by Jaguar the previous year. He also played a key role in recruiting Adrian Newey, who was announced as the team’s chief technical officer in November 2005.

2006 was a transitional year: by the time Newey started work at Red Bull in February 2006, that year’s car (the RB2) had already been designed, and the team switched from Cosworth to customer Ferrari engines, which overheated and were unreliable. However the team did take its first podium finish at the Monaco Grand Prix, where Horner jumped into a swimming pool wearing nothing but a Superman cape to celebrate.

2007 brought the RB3, the team’s first Newey-designed car, and the arrival of Mark Webber and Renault engines, however the team continued to suffer from problems with reliability, with the car enduring 14 retirements and scoring a single podium, whilst the team dropped down to seventh in the Constructors’ Championship the following year.

The team finished a strong second in the 2009 Constructors’ Championship with drivers Sebastian Vettel and Mark Webber finishing second and fourth respectively in the drivers’ title race, and taking six wins between them. In 2010, the team won their first Constructors’ Championship with one race to spare, and Sebastian Vettel won the Drivers’ Championship at the final race of the season, becoming the youngest World Champion. At 36, Horner was the youngest team principal to win a Formula 1 Constructors’ Championship. In 2011, the team won their second Constructors’ Championship with three races to spare, with Sebastian Vettel becoming the world’s youngest double-champion. In 2012 the team won their third Constructors’ Championship with one race to spare. Sebastian Vettel became the world’s youngest triple World Champion. In 2013 Red Bull Racing won its fourth consecutive F1 Constructors’ Championship as Sebastian Vettel won his fourth Drivers’ Championship.

With his former partner Beverley Allen, Horner has a daughter, born in October 2013. Horner and former Spice Girls member Geri Halliwell announced their engagement on 11 November 2014, and were married on 15 May 2015 in Woburn, Bedfordshire. On 10 October 2016, Halliwell announced the pair were expecting their first child together, their son was born in January 2017. Horner is stepfather to Halliwell’s daughter, Bluebell Madonna, from her previous relationship with screenwriter Sacha Gervasi. Horner is an avid Coventry City F.C. supporter.

Horner was appointed Officer of the Order of the British Empire (OBE) in the 2013 Birthday Honours for services to motorsport.