Despite the E20's passive Drag Reduction System device — referred to internally as "The Device" — spending virtually the entire 2012 season in development without being raced, the E21 was launched with a similar passive DRS system incorporated into its design. The concept was finally raced at the 2013 British Grand Prix, fitted to Räikkönen's car, with the second car run without it to allow a direct performance comparison.
The 2013 technical regulations permitted teams to use a so-called modesty panel — a small carbon-fibre fairing designed to cover the stepped nose profile that had drawn criticism on the 2012 generation of cars. Lotus opted not to fit one, judging that the panel offered no aerodynamic gain and that the minor aesthetic benefit did not justify the weight addition.
The E21 was driven by 2007 World Champion Kimi Räikkönen and Romain Grosjean, both continuing with the team from 2012. The car opened the season with a race victory at the Australian Grand Prix and went on to score fourteen podiums across the year. Lotus finished fourth in the Constructors' Championship with 315 points.
Räikkönen remained a championship threat for much of the year before departing for Ferrari after the season, making the E21 his final car in the black and gold Lotus livery. The team's financial pressures, which had become visible in the second half of 2012, continued to shadow the squad through 2013.
The E21 retained the black and gold John Player Special-inspired colour scheme from the previous car, with the addition of subtle red accents as the main livery change for 2013.
At Monaco, Lotus partnered with electronic music duo Daft Punk to mark the release of their album Random Access Memories. The Daft Punk logo appeared on the rear wing, and the helmet designs from the album cover were reproduced on both sides of the car. At the Korean Grand Prix, the Renault engine branding was badged as Renault Samsung, mirroring the same arrangement used simultaneously on the Caterham CT03.
A recurring feature of the E21's livery throughout the season was a changing hashtag on the bodywork at each race, often referencing local cuisine or cultural references through puns. During pre-season testing in Jerez, the hashtag read "#SexyAndIKnowIt"; at Abu Dhabi, timed to coincide with Halloween, it carried "#AlloWin?" accompanied by a pumpkin graphic, playing on the French phrase "Allô Win? Ici Trouille!"
During the summer of 2013, businessman Mansoor Ijaz, leading a group called the Quantum Motorsports consortium, announced a proposed acquisition of a 35 percent stake in the Lotus F1 Team from majority owner Genii Capital. The deal was repeatedly delayed and was never completed despite Ijaz's claims that his side had fulfilled its obligations. The failed transaction added further uncertainty to the team's already strained financial position heading into 2014.