Motor racing near Estoril dates to the 1930s, when a 2.8 kilometre street circuit was used in 1937 for a local event. The permanent Estoril circuit was built and completed in 1972 on a plateau near the resort town, retaining the name of that earlier tradition. Its original perimeter measured 4.349 kilometres, with a maximum gradient approaching 7 per cent, giving it two notable hairpin turns and significant elevation changes. The circuit fell into disrepair after its ownership passed to the state between 1975 and 1978, and it required substantial redevelopment before international motorsport could return in 1984.
Another street circuit in Lisbon, the Monsanto Park course, had hosted the 1959 Portuguese Grand Prix, briefly sharing that role with the Boavista street circuit in Porto before Estoril became the settled home of the race.
Estoril's thirteen-year run as an annual Formula One venue, from 1984 to 1996, produced a remarkable concentration of historic moments.
The 1984 Portuguese Grand Prix was the scene of one of the most dramatic championship conclusions of the decade. Niki Lauda won the 1984 World Championship from his McLaren teammate Alain Prost by just half a point — the narrowest margin in the championship's history — after finishing second to Prost in that race, earning the points he needed to secure his third and final title.
The following year brought Ayrton Senna's first Formula One victory, achieved at Estoril in the 1985 Portuguese Grand Prix driving for Lotus. The victory was the beginning of one of the sport's most dominant careers.
Later editions brought further controversy. The 1989 race was marked by Nigel Mansell receiving a black flag for a dangerous overtaking manoeuvre and subsequently colliding with Senna. In 1992, Riccardo Patrese was launched airborne in a near-backward flip after colliding with Gerhard Berger on the main straight. The 1996 race, the last Portuguese Grand Prix held at Estoril, saw Jacques Villeneuve execute a celebrated overtake on Michael Schumacher around the outside of the final turn.
After a safety chicane was added following Ayrton Senna's death at the 1994 San Marino Grand Prix, the circuit's length increased to 4.360 kilometres. Estoril was dropped from the Formula One calendar for 1997. A new redesign of the parabolica turn, implemented in 2000 to obtain FIM homologation, reduced the circuit to its current length of 4.182 kilometres.
Estoril was popular with Formula One teams as a winter testing venue due to its generally dry climate and accessible location. The circuit's combination of a long straight, hairpins, and flowing medium-speed corners offered a useful range of setup evaluation. Strong coastal winds occasionally affected running conditions.
The circuit had recurring safety-related complications throughout its F1 tenure, failing safety inspections on more than one occasion, which contributed to debate about its suitability for top-level competition.
After losing the Formula One Grand Prix, Estoril continued to host significant international motorsport. The FIA GT Championship, the Deutsche Tourenwagen Masters, the World Series by Renault, and the Superbike World Championship all appeared at the circuit during the 2000s.
On 3 September 2000 the circuit held its first Portuguese motorcycle Grand Prix, an event that ran annually through 2012. In 2005 Estoril hosted a round of the inaugural A1 Grand Prix season. The 2020 season, disrupted by the COVID-19 pandemic, brought the final round of that year's Superbike World Championship and the concluding race of the 2019-20 FIM Endurance World Championship to the circuit.
Estoril remains an active venue hosting national and international categories including the Superbike World Championship, winter testing series, and various Portuguese national championships.