2021 Audi A4

Showing the 2021 A4 Premium Plus. We haven't verified this trim's engine; the numbers below cover every version of this model year. Every version

Owner complaints, recalls, fuel economy and safety ratings from public NHTSA and EPA data, updated Oct 17, 2026.

Fuel economy
26–28 mpgcombined; city 24–25, highway 30–34; every version of this model year
Five years of fuel
$14,370–$15,480U.S. average; Ohio $13,540–$14,580 at local prices; every version of this model year; fuel only, not other costs of owning it; 15,000 miles a year, at EIA fuel prices for the week of Oct 12, 2026
NHTSA overall safety rating
5 starslowest across the versions NHTSA tested
Recall campaigns
4over its history; check a VIN for open ones
Owner complaints
12filed with NHTSA; not adjusted for sales

Trims

NHTSA's VIN data lists these trims for the 2021 A4. A trim's engine and numbers are shown as its own only where EPA names versions after the trim and no other version could be it; "seen with" means a source shows that engine on the trim, not that it was the only one. Recalls and complaints cover the whole model year: whether a recall applies to a car depends on its VIN, on NHTSA's recall lookup.

Problems owners report

Owners have filed 12 complaints with NHTSA about the 2021 A4. These are unverified owner reports, counted by the part of the car they name; one complaint can name several parts. Counts aren't adjusted for how many were sold, so they don't show how reliable a car is.

Complaints by part of the car
PartComplaintsCrashesFiresInjuries
Electrical system3000
Forward collision avoidance3000
Unknown or other3100
Lane departure2000
Power train2000
Suspension2101
Vehicle speed control2201
Air bags1100
Engine1000
Tires1000

Complaints by model year

Newer years have had less time to collect complaints, and counts aren't adjusted for sales, so a shorter bar doesn't mean a more reliable year.

  1. 2006298
  2. 2007219
  3. 2008191
  4. 2009144
  5. 201064
  6. 201143
  7. 201245
  8. 2013111
  9. 201478
  10. 201544
  11. 201626
  12. 201786
  13. 201854
  14. 201913
  15. 2020158
  16. 202112
  17. 20227
  18. 202311
  19. 20246
  20. 20251

Every A4 year side by side

Recalls

NHTSA lists 4 recall campaigns for the 2021 A4 over its history. Campaigns are matched by model and year, so each one may apply to a given car, and its repair may already be done: check a VIN on NHTSA's recall lookup for the open recalls on that exact car.

Back over prevention: display function

NHTSA campaign 22V742000 · reported Oct 5, 2022 · 170,296 vehicles potentially affected

Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2021 Audi A8, RS7, RS6 Avant, RS5 Sportback, RS5 Coupe, Q8, Q7, Q5 Sportback, S4 Sedan, Q5, A7, A6, A6 Allroad, A5 Sportback, A5 Coupe, A5 Cabrioleet, A4 Sedan, A4 Allroad, E-Tron Sportback Quattro, SQ7, S5 Cabriolet, E-Tron Quattro, SQ8, SQ5 Sportback, SQ5, S8, S7, S6 Sedan, S5 Sportback, S5 Coupe, 2022 E-Tron GT, and 2021-2022 RSQ8 vehicles. Due to a software issue, a blank or black screen may be displayed instead of the rearview camera image when the vehicle is placed in reverse gear. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."

Risk: A blank rearview camera display can reduce the driver's rear visibility, increasing the risk of a crash.

Remedy: Dealers will update the infotainment unit software, free of charge. Owner notification letters were mailed October 25, 2022. Owners may contact Audi's customer service at 1-800-253-2834. Volkswagen's number for this recall is 91DZ.

NHTSA's record and documents

Suspension: rear; Tires

NHTSA campaign 22V034000 · reported Jan 26, 2022 · 31,058 vehicles potentially affected

Volkswagen Group of America, Inc. (Audi) is recalling certain 2019-2021 Audi A5 Sportback, RS5 Coupe, RS5 Sportback, S5 Sportback, 2020-2021 A4 Allroad, A4 Sedan, A5 Cabriolet, A5 Coupe, A6 Allroad, A6 Sedan, A7, A8, Q5, S4 Sedan, S5 Coupe, S5 Cabriolet, S6 Sedan, S7, S8, SQ5, 2021 Q5 Sportback, Q7, Q8, RS6 Avant, RS7, RSQ8, SQ5 Sportback, SQ7, and SQ8 vehicles. The rear axle alignment may not have been inspected after the repairs for Recall 21V-295 (42L1) were performed.

Risk: Rear axle misalignment may cause premature or uneven tire wear, increasing the risk of a crash.

Remedy: Dealers will inspect the rear axle, adjust the alignment as necessary, and replace any prematurely or unevenly worn tires, free of charge. Owner notification letters were mailed March 3, 2022. Owners may contact Audi customer service at 1-800-253-2834. Audi's number for this recall is 42L5.

NHTSA's record and documents

Seat belts; Seat belts: rear/other

NHTSA campaign 21V606000 · reported Aug 5, 2021 · 45,496 vehicles potentially affected

Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2021 Volkswagen ID4, Audi A4 Allroad, A4 Sedan, A5 Cabriolet, A5 Coupe, A5 Sportback, A6 Allroad, A6 Sedan, A7, A8, E-Tron Quattro, E-Tron Sportback Quattro, Q3, Q5, Q5 Sportback, Q7, Q8, RS5 Sportback, RS5 Coupe, RS6 Avant, RS7, RSQ8, S4 Sedan, S5 Cabriolet, S5 Coupe, S5 Sportback, S6 Sedan, S7, S8, SQ5, SQ5 Sportback, SQ7, SQ8, and 2021-2022 S3 Sedan vehicles. The rear seat belt automatic locking retractors may deactivate early, which can prevent the child restraint system from securing properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."

Risk: An unsecured child restraint system can increase the risk of injury during a crash.

Remedy: Dealers will inspect, and replace as necessary, the middle-rear seat belt assemblies, free of charge. Owner notification letters were mailed August 27, 2021. Owners may contact Volkswagen customer service at 1-800-893-5298 and Audi customer service at 1-800-253-2834. Volkswagen's numbers for this recall are 69CR (VW) and 69CS (Audi).

NHTSA's record and documents

Suspension: rear

NHTSA campaign 21V295000 · reported Apr 26, 2021 · 40,993 vehicles potentially affected

Volkswagen Group of America, Inc. (Audi) is recalling certain 2021 Q7, Q8, Q5 Sportback, SQ5 Sportback, RS6 Avant, RS7, RS Q8, 2020-2021 Audi S6 sedan, Q5, A8, S8, A7, A6 Allroad, A5 Cabriolet, A4 sedan, A4 Allroad, SQ5, S7, A6 sedan, S5 coupe, S4 sedan, S5 Cabriolet, A5 coupe, 2019-2021 RS5 coupe, A5 Sportback, S5 Sportback, RS5 Sportback vehicles. The lock nut on the trailing arm of the rear axle may break due to stress corrosion.

Risk: A broken lock nut may misalign the rear axle, causing a loss of control and increasing the risk of a crash.

Remedy: Dealers will replace the lock nuts and, if necessary, the associated bolts, free of charge. Owner notification letters were mailed June 4, 2021. Owners may contact Audi customer service at 1-800-253-2834. Audi's number for this recall is 42L1.

NHTSA's record and documents

Service bulletins and investigations

Carmakers sent NHTSA 1,067 service bulletins and notices that cover the 2021 A4, the latest on Sep 25, 2026. They tell dealers how to fix known issues.

The parts they mention most: electrical system (346), equipment (254), unknown or other (111), structure (90), power train (58).

NHTSA hasn't opened a defect investigation that covers this model year.

Maintenance

Oil

The owner's manual gives the oil and how often to change it. We show oil facts only once we've checked them against the manual, and we haven't yet for the 2021 A4.

Oil change near you: Jiffy Lube · Take 5

Specs

EPA class: compact cars. EPA greenhouse gas score: 5–6 out of 10. Each version EPA tested:

VersionEngineTransmissionFuelCity / hwy / comb
A4 allroad quattro
All-Wheel Drive
2.0 L, 4 cyl, turboAutomatic (AM-S7)Premium Gasoline24 / 30 / 26
A4 quattro
All-Wheel Drive
2.0 L, 4 cyl, turboAutomatic (AM-S7)Premium Gasoline25 / 34 / 28
A4 S line quattro
All-Wheel Drive
2.0 L, 4 cyl, turboAutomatic (AM-S7)Premium Gasoline24 / 31 / 27

Sources and dates

Fuel cost: EPA mpg with fuel prices for the week of Oct 12, 2026 and electricity prices for Jul 2026. Source: U.S. Energy Information Administration (Oct 2026). Complaints are unverified reports owners filed with NHTSA. About the data