The Fw 190 A-3 was equipped with the BMW 801 D-2 engine, which increased power to 1,700 PS (1,700 hp; 1,300 kW) at takeoff by improving the supercharger and raising the compression ratio. Because of these changes, the A-3 model required a higher octane fuel—100 (C3) versus 87 (B4). The A-3 retained the same weaponry as the A-2. The A-3 also introduced the Umrüst-Bausätze factory conversion sets. The Fw 190 A-3/U1 and U2 were single experimental Fw 190s: U1 (W.Nr 130270) was the first 190 to have the engine mount extended by 15 cm (5.9 in), which would be standardized on the later production A-5 model. The U2 (W.Nr 130386) had RZ 65 73 mm (2.9 in) rocket launcher racks under the wings with three rockets per wing. There were also a small number of U7 aircraft tested as high-altitude fighters armed with only two 20 mm MG 151 cannon, but with reduced overall weight.

The Fw 190 A-3/U3 was the first of the Jabo (Jagdbomber), using an ETC-501 centerline bomb rack able to carry up to 500 kg (1,100 lb) of bombs or, with horizontal stabilizing bars, one 300 L (80 US gal) drop tank. The U3 retained the fuselage-mounted 7.92 mm (.312 in) MG 17s and the wing-mounted 20 mm MG 151 cannon, with the outer MG FF being removed.

The Fw 190 A-3/U4 was a reconnaissance version with two RB 12.5 cameras in the rear fuselage and an EK 16 gun camera or a Robot II miniature camera in the leading edge of the port wing root. Armament was similar to the U3, however, and the ETC 501 was usually fitted with a 300 L (80 US gal) drop tank. See A-2 for production numbers.

In autumn 1942, a political decision diverted 72 new aircraft to Turkey in an effort to keep that country friendly to the Axis powers. These were designated Fw 190 A-3a (a=ausländisch (foreign), designation for export models) and delivered between October 1942 and March 1943. The Turkish aircraft had the same armament as the A-1: four 7.92 mm (.312 in) synchronized MG 17 machine guns and two 20 mm MG FF cannon. There was no FuG 25 IFF device in the radio equipment.