NHTSA // CRASH-TESTED
2021 Audi S4 Safety Ratings
The 2021 Audi S4 scores 96 out of 100 on the NHTSA Safety Index (Exceptional), 4 recalls, and 2 owner complaints on file.
Updated Oct 1, 2026 from NHTSA data · Reviewed by Ivanna Verstliar
The 2021 Audi S4 achieved an Exceptional rating in the NHTSA Safety Index, scoring 96 out of 100. This is underpinned by perfect scores in both crash-avoidance technology and crash protection, based on the ratings NHTSA published. While its overall safety profile is robust, four recalls are on record for this model year; prospective owners should confirm all necessary remedies have been applied.
The 2021 Audi S4 receives a NHTSA Safety Index of 96 out of 100 and a 5-out-of-5-star NHTSA rollover rating, sourced from NHTSA crash-test and recall data.
MotorCaliber Safety Desk // NHTSA data, verified Oct 1, 2026
Among the 94 Sedans from 2021 that NHTSA has crash-tested, the 2021 Audi S4 ranks 8 for overall NHTSA Safety Index.
- families prioritizing rollover safety
- new and teen drivers who want standard crash-avoidance tech
| NHTSA Safety Index | 96 / 100 (Exceptional) |
|---|---|
| Frontal / Side / Rollover | 5 stars |
| Rollover risk | 9.9% |
| Recalls on file | 4 |
| Owner complaints | 2 (unverified allegations) |
| Class rank | 8 of 94 Sedans tested for 2021 |
| Data verified | Oct 1, 2026 |
ANALYSISHow safe is the 2021 Audi S4?
The 2021 Audi S4 achieved a perfect 70 out of 70 for crash protection and a 10 out of 10 for crash-avoidance technology, contributing to its NHTSA Safety Index of 96/100. This places it in the Exceptional band, matching the 2020 model year. The only component preventing a ceiling score is its defect record, which earned 16 out of 20. This sub-score reflects four recall campaigns covering backup camera display function, tire concerns, rear seat-belt retractors, and rear suspension axle assembly. NHTSA published only one specific NCAP crash data point for this model year: a 5 out of 5 stars rollover rating with a 10 percent risk. No overall, frontal, or side crash ratings were conducted. Owner complaints remain low, with just two reported and zero alleged injuries, though the recall count represents the most significant safety consideration for this vehicle.
NCAP // CRASH TESTHow did the 2021 Audi S4 perform in crash tests?
The 2021 Audi S4 achieved the top 5 out of 5 stars in NHTSA's rollover test, with a 10 percent rollover risk and a "No Tip" result in the dynamic tip test. However, NHTSA did not assign ratings for overall, frontal, or side crash protection for this model year. These critical safety dimensions remain unrated.
Source: NHTSA NCAP, VehicleId 15587
Index breakdown
NHTSA // RECALLSDoes the 2021 Audi S4 have any recalls?
Yes. Four recall campaigns cover the 2021 Audi S4. Components affected include: backup camera display function, tires, rear seat-belt retractors, and rear suspension axle assembly. No park-outside or do-not-drive directive is indicated in the available campaign data. All four campaigns should be verified as remedied on any specific vehicle using its VIN at NHTSA.
BACK OVER PREVENTION:DISPLAY FUNCTION22V742000
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.
Reported 2022-10-05
TIRES22V034000
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.
Reported 2022-01-26
SEAT BELTS:REAR/OTHER:RETRACTOR21V606000
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).
Reported 2021-08-05
SUSPENSION:REAR:AXLE:NON-POWERED AXLE ASSEMBLY21V295000
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.
Reported 2021-04-26
NHTSA // COMPLAINTSWhat do owners report about the 2021 Audi S4?
Two unverified consumer allegations have been reported to NHTSA for the 2021 Audi S4. The top reported components are the Electrical System, cited in one allegation, and an Unknown or Other category, cited in one allegation. No crashes, fires, injuries, or deaths are alleged. These are unverified consumer reports, not established facts.
2 owner complaints on file. These are unverified allegations reported to NHTSA.
USED BUYERWhat should used buyers know about the 2021 Audi S4?
Because this is a 5-year-old vehicle, all four recall campaigns may or may not have been completed by previous owners. Run the specific VIN through NHTSA's recall lookup tool before purchase to confirm remedy status on the seat-belt retractor, tire, backup camera, and rear suspension campaigns. An unresolved recall is a safety item, not a negotiating footnote.
- The 2021 Audi S4 Safety Index of 96/100 held flat versus the 2020 model year, with the defect record sub-score of 16/20 being the sole drag on a near-perfect composite, driven by four active recall campaigns specific to this model year.
- NHTSA did not conduct overall, frontal, or side crash tests on the 2021 Audi S4; the only rated dimension is rollover, which earned the maximum 5 out of 5 stars with a 10 percent rollover risk.
- The four 2021-specific recalls touch safety-critical systems including rear seat-belt retractors and rear suspension axle assembly, making VIN-level remedy verification a required step for any used-market buyer.
- The reported complaint volume for this model year is exceptionally low at two total allegations, with no reported crashes, fires, injuries, or fatalities, though complaints represent unverified consumer reports to NHTSA and low volume does not guarantee an absence of issues.
RANKINGSWhere the 2021 Audi S4 places
The 2021 Audi S4 qualifies for these MotorCaliber safety rankings:
FAQ2021 Audi S4 safety questions
Was the 2021 Audi S4 crash-tested by NHTSA?
Yes. NHTSA crash-tested the 2021 Audi S4, and it earns a NHTSA Safety Index of 96 out of 100, placing it in the Exceptional band. The index combines federal crash-test stars, standard crash-avoidance tech, and the recall record.
What are the 2021 Audi S4 crash-test star ratings?
In NHTSA testing the 2021 Audi S4 earned 5 out of 5 stars for rollover. Its measured rollover risk is 9.9%. Categories NHTSA did not test show as not rated.
How many recalls does the 2021 Audi S4 have?
According to NHTSA recall data, 4 vehicle recalls are on file for the 2021 Audi S4. Confirm your VIN at nhtsa.gov to see which apply to your car.
How many complaints have owners filed about the 2021 Audi S4?
According to NHTSA's complaint database, 2 owner complaints are on file for the 2021 Audi S4. These are unverified allegations submitted by owners, not confirmed defects.
Cross-check this record against independent expert reviews and the live NHTSA database before you buy.
Other S4 years
Rivals in Sedan (2021)
| Vehicle | NHTSA Safety Index | Overall stars | Recalls |
|---|---|---|---|
| 2021 Audi RS 5 Sportback | 100/100 | not rated | 0 |
| 2021 Audi S5 Sportback | 100/100 | not rated | 0 |
| 2021 Nissan Maxima | 100/100 | 5 of 5 | 0 |
| 2021 Audi A4 Allroad | 99/100 | not rated | 1 |
| 2021 Cadillac CT5-V | 97/100 | not rated | 0 |
| 2021 Infiniti Q50 | 97/100 | not rated | 3 |
- DATA Pulled directly from NHTSA: New Car Assessment Program crash tests (VehicleId 15587), the recallsByVehicle and complaintsByVehicle records for the Audi S4 2021.
- SCORE The NHTSA Safety Index (0-100) weights crash protection, standard crash-avoidance tech, and the defect record. Full formula on the methodology page. It ranks 8 of 94 in the Sedan class for 2021.
- EDITED Written by the MotorCaliber Safety Desk and reviewed for accuracy and plain-language clarity by Ivanna Verstliar, Editor, against the source figures on this page.
- VERIFIED Data last synced Oct 1, 2026. Recalls change; confirm your VIN at nhtsa.gov/recalls. See our corrections policy and disclosure.