The Avant is sporty looking wagon with a steeply sloped rear hatch that sacrifices some cargo room for a slick, up-market profile. Overall, the Avant is the same length as the sedan. Its rear hatch can open at two different heights, to allow extra clearance for taller owners. It also features a dual-loading cargo floor, a rakish roof-mounted antenna and unique window trim: black on 1.8T, brushed aluminum on 3.0 and S4.

Cabriolet models share the sedan's basic lines and clean, taut surfaces in a two-door convertible body style. The wide arc of the soft top accentuates the A4's pure proportions and subtle wedge shape. Cabriolets come with unique features. Among them: brushed aluminum trim around the windscreen and waist. The cabrio's body-colored air dam, especially in the lighter paint colors, accentuates the openings under the front bumper more than the dark-colored air dam on the sedan and Avant.

S4 models are distinguished by fully painted bumpers, xenon headlights with contrasting titanium-colored inner housings, aluminum-finish exterior mirrors, and a trunk-mounted rear spoiler. The S4 Avant is further distinguished by its aluminum-colored roof rails.

Safety features that come standard on all A4/S4 models include antilock brakes, Brake Assist, and Electronic Brake force Distribution (EBD); an electronic stability program (ESP); dual front airbags that deploy at different rates depending on the severity of a crash, front side-impact airbags, and three-point seat belts at all five locations with pre-tensioners and force limiters in front. Sedans and Avants also have curtain-style head-protection airbags for front and rear-seat passengers, while the Cabriolet's seat-mounted side-impact airbags are designed to provide head protection. The Cabriolet features an active rollover protection system located in the double rear bulkhead. Should the car roll, electronic sensors trigger two protective hoops that pop up from behind the rear seats in less than a second. Together with the extremely rigid windscreen frame, these hoops help to maintain an intact survival zone designed to protect all occupants. Rear side-impact airbags are optional ($350) on all models except the Cabriolet.