The SX4 continues Suzuki's focus on mini SUVs and subcompact SUVs, like Jimny/SJ, and Vitara/Escudo.[9] The car was created as a result of a joint development agreement between Suzuki and Fiat signed in April 2003.[8] It was introduced in Japan on 1 December 2005,[10] and internationally at the 76th Geneva Motor Show in March 2006. Designed by Giorgetto Giugiaro's Italdesign studio, the SX4 replaces the Aerio (Liana in some markets). Although originally intended solely for Europe, the SX4 is sold in most of Suzuki's international markets. Especially as a 4WD hatchback, the SX4 occupies a specific market niche of mini SUVs. Depending on the market, it was available with petrol engines in the 1.0 to 2.0 L range, and Fiat/Peugeot's 1.3 to 2.0 L diesels.

Based on the Suzuki Swift, it was manufactured at the Magyar Suzuki plant in Esztergom, Hungary; Manesar, India; Bekasi, Indonesia; Chongqing, China and Sagara, Japan. Production in Hungary was expected to be 60,000 units per year — two-thirds to be sold by Suzuki and one-third by Fiat, badged as the Sedici.[11]

The SX4 Crossover had also been sold in Indonesia since 2007. Earlier models were directly imported from Japan and marketed as the SX4 X-Over. However, locally assembled versions were introduced a year later due to higher market demand. The locally assembled versions were then equipped with four-wheel disc brakes and a multi-information display. The Indonesian-produced SX4 was also exported to Thailand. The SX4 sedan was also sold in Indonesia as the Suzuki Neo Baleno from 2008 until 2011.

Engines included the 1.5 L gasoline version that was identical to the one used in the Swift, a 1.6 L gasoline (with VVT) with a maximum output of 102 PS (75 kW; 101 hp) (which powers the SX4 Sedan sold in India by Maruti), the 1.6 L VVT version also used in the new Grand Vitara, and a 107 PS (79 kW; 106 hp), 1.9 L DDIS — along with the Fiat diesel engine with a maximum output of 120 PS (88 kW; 118 hp) and maximum torque of 280 N⋅m (210 lb⋅ft).

The SX4 was initially released as a five-door hatchback body style, marketed as the SX4 Crossover. With boot space of 300 L (270 L VDA) and 60:40 split-fold rear seats, they have a tumble/roll configuration that allows for a flat load area up to a maximum volume of 1045 L(625 L VDA).[12]

The sedan model, marketed as the SX4 Sport, debuted at the 2007 New York International Auto Show and was released in Japan, India, and a few Eastern European markets.[13] It replaced the Suzuki Aerio sedan and also the Daewoo-based Suzuki Forenza sedan and station wagon.[14]