The Bell 430 features several significant improvements over the 230, the most significant of these being the new four-blade, bearingless, hingeless, composite main rotor. Although both the 230 and 430 are powered by Rolls-Royce (Allison) 250 turboshaft engines, the 430's engines are 10% more powerful. Other changes include the 1 ft 6 in (46 cm) stretched fuselage, providing for two extra seats, an optional EFIS flight deck, and a choice of either skids or retractable wheeled undercarriage.
The typical configuration seats ten, including a pilot and co-pilot with eight passengers in the main cabin behind them in three rows of seats. Six- and eight-place executive layouts are offered. In an EMS role it can carry one or two stretcher patients with four or three medical attendants, respectively. Maximum external load capacity is 3,500 lb (1,585 kg).