When BMW acquired the Sauber team ahead of the 2006 season, the incoming car originally carried the internal Sauber designation C25 before being renamed the F1.06 to reflect BMW's ownership. The chassis was designed by Willy Rampf, Jacky Eeckelaert, and Seamus Mullarkey, with the powertrain engineered by Heinz Paschen. The F1.06 was the first V8-powered car produced at the team's Hinwil base since the Sauber C14 in 1995, and the first non-Ferrari-engined car from Hinwil since the Ford Cosworth-powered Sauber C15 in 1996.
The 2006 season was treated by the team as a transitional year, making its ultimate level of competitiveness a welcome surprise. The F1.06 was a consistent points contender and delivered two podium finishes: Nick Heidfeld took third at the Hungarian Grand Prix, and Robert Kubica claimed third at the Italian Grand Prix at Monza. Kubica had been called up to replace Jacques Villeneuve mid-season following a crash at the German Grand Prix that effectively ended Villeneuve's Formula One career.
BMW Sauber developed the car steadily throughout the season with upgrades at virtually every round. The team's technical ambition also produced controversy: a rear wing judged to be illegally flexible was stiffened early in the season, and two vertical aerodynamic pylons fitted in front of the cockpit made their only appearance at Magny-Cours before the FIA banned them on safety grounds, ruling that they obstructed the drivers' vision. The team finished the year fifth in the Constructors' Championship with 36 points.
Nick Heidfeld joined from Williams as the team's lead driver. Jacques Villeneuve, who had driven for Sauber the previous season before the BMW takeover, started the year as his teammate but was dropped after the German Grand Prix crash. Robert Kubica, who served as the team's third driver, was elevated to a race seat and completed the season alongside Heidfeld.
The F1.06 adopted BMW's traditional blue and white colour scheme with red accents, a livery that the team would maintain throughout its tenure in Formula One. Key sponsors included Credit Suisse and Petronas, both carried over from the Sauber era, alongside new partners Intel and O2. During qualifying at the Brazilian Grand Prix, both cars displayed the message "Danke Michael / Thanks Michael" on their rear wings in tribute to the retiring Michael Schumacher.
The F1.06 was the last car at the Hinwil facility to be developed primarily by the existing Sauber engineering staff before BMW fully assumed control of technical operations. It demonstrated that the transition from independent constructor to BMW factory team could be achieved without sacrificing competitiveness, setting the stage for more ambitious campaigns in the seasons that followed.