The A320 series has two variants, the A320-100 and A320-200. Only 21 A320-100s were ever produced these aircraft, the first to be manufactured, were delivered only to Air Inter (later acquired by Air France) and British Airways (as a result of an order from British Caledonian Airways made prior to its acquisition by British Airways). The A320-200 features wingtip fences and increased fuel capacity over the A320-100, resulting in increased range otherwise differences are minimal. Typical range with 150 passengers for the A320-200 is about 3,300 nautical miles (6,150 km). It is powered by two CFMI CFM56-5s or IAE V2500s with thrust ratings between 113 to 120 kN (25,400 to 27,000 lbf). The direct Boeing competitor is the 737–800.

The A321 is stretch and first derivative of the standard A320. The variant was launched in 1988,[33] when the A320 began operations. Compared with the A320, the A321's major change is the stretched fuselage, which is lengthened by 6.94 metres (22 ft 9 in).[46][47] This is achieved by adding a front plug immediately forward of wing 4.27 m (14 ft 0 in), and a 2.67 m (8 ft 9 in) rear plug.[103] To maintain performance, double-slotted flaps were included, in addition to increasing the wing area by 4 m2 (43 sq ft), to 128 m2 (1,380 sq ft).[45] Other minor modifications were made to accommodate the A321's 9,600 kg (21,200 lb) increase in maximum takeoff weight, taking the MTOW to 83,000 kg (183,000 lb).[44] The maiden flight of the first of two prototypes came on 11 March 1993.[41] The A321 entered service in 1994.