The BMW 4-Series convertible (formerly 3-Series) is a compelling choice for drivers looking for open-air motoring with the security of a retractable hardtop. Competition includes the convertible models of the Audi A5, Mercedes-Benz E-Class, and Infiniti Q60. Available with turbocharged 4-cylinder (428i) and 6-cylinder (435i) engines, the convertible retains most of the performance and handling of the coupe. Torsional and bending rigidity is surprisingly good for a convertible, but this convertible weighs in at 2 tons. A comprehensive set of active safety enhancements ensure the best possible accidence avoidance capabilities.

New engines force an updated nomenclature. Four cylinder models are now 430i (formerly 428i), whereas six-cylinder engines become 440i (formerly 435i).