The 2018 season saw the retirement of the long-serving Dallara GP2/11 chassis, which had been in use since 2011, and the naturally aspirated V8 engine that dated to 2005. Both were replaced by the Dallara F2 2018, powered by a 3.4-litre V6 turbocharged engine — designated V634T — developed by Mecachrome. The fuel-efficient turbocharged package represented a generational shift in the series' technical identity. Pirelli continued as tyre supplier, with tyre sizes unchanged from the pre-2017 Formula 1 specification. Elf remained as the official fuel partner.
The Halo cockpit protection device was mandated for all competitors. The Halo — a wishbone-shaped frame mounted above the cockpit and anchored to the monocoque — had been developed for and introduced in Formula 1 that same year, then applied across FIA-affiliated open-wheel categories. The new Dallara chassis incorporated the Halo as part of its original design. Following early criticism of the F2 2018's difficult start procedure and reliability issues, rolling starts were temporarily introduced while solutions were found.
The championship also discontinued the use of grid models in 2018, following the same decision made by Formula 1 management.
Charles Leclerc was the reigning drivers' champion, having clinched the 2017 title at Jerez before moving to Formula 1 with Alfa Romeo Sauber. Russian Time were the reigning teams' champions.
The 2018 season produced one of the more talent-dense grids in the series' history. George Russell, promoted from GP3 with ART Grand Prix, won seven Feature races en route to the drivers' title, finishing 68 points clear of Lando Norris. Alexander Albon, who moved from ART to DAMS, won four races. Nyck de Vries and Artem Markelov each won three, Antonio Fuoco two, and single wins went to Norris, Jack Aitken, Maximilian Gunther, Nicholas Latifi, and Tadasuke Makino. Carlin beat ART Grand Prix by 31 points in the teams' standings.
A notable incident came at Silverstone, where Santino Ferrucci deliberately made contact with Arjun Maini on the cool-down lap. Ferrucci was suspended for two rounds and subsequently dismissed by Trident, with sponsorship cited as the official reason.
The 2018 calendar expanded to twelve rounds, adding the Circuit Paul Ricard for the French Grand Prix and the Sochi Autodrom for the Russian Grand Prix. The stand-alone Jerez event from 2017 was discontinued. Each round comprised a Feature race of approximately 170 km including a mandatory pit stop, and a Sprint race of approximately 120 km without a pit stop requirement. The Sprint race grid was set by reversing the top eight positions from the Feature race result.
The entry comprised twenty drivers across ten teams. Carlin returned after a one-year absence, while the Czech team Charouz Racing System entered Formula 2 for the first time, filling the vacancy left by Rapax. Racing Engineering and Fortec Motorsports both withdrew before the season began. Numerous prominent junior drivers moved into or between seats: Lando Norris joined Carlin fresh from winning the 2017 FIA Formula 3 European Championship; Alexander Albon moved to DAMS; Nyck de Vries joined Prema alongside Sean Gelael; and Louis Deletraz and Antonio Fuoco were placed with Charouz as part of Ferrari's driver development programme.