2021 BMW 4 Series

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

Fuel economy
26–29 mpgcombined; city 23–26, highway 31–34; every version of this model year
Five years of fuel
$13,880–$15,480U.S. average; Ohio $13,070–$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
Not ratedNHTSA has no overall rating for this year
Recall campaigns
7over its history; check a VIN for open ones
Owner complaints
21filed with NHTSA; not adjusted for sales

Problems owners report

Owners have filed 21 complaints with NHTSA about the 2021 4 Series. 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 system7000
Engine5010
Seat belts4000
Power train2000
Unknown or other2000
Forward collision avoidance1000
Seats1000
Service brakes1102
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. 201459
  2. 201594
  3. 201654
  4. 201730
  5. 201843
  6. 201926
  7. 20205
  8. 202121
  9. 20228
  10. 20236
  11. 20243
  12. 20258
  13. 20262

Every 4 Series year side by side

Recalls

NHTSA lists 7 recall campaigns for the 2021 4 Series 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.

Electrical system: starter assembly

NHTSA campaign 26V056000 · reported Jan 30, 2026 · 87,394 vehicles potentially affected

BMW of North America, LLC (BMW) is recalling certain 2021-2023 Toyota Supra, 2022-2023 2 Series Coupe, 2021-2024 5 Series (xDrive), 2021-2022 Z4, 2022-2024 4 Series (Gran Coupe), 2021-2024 4 Series (Convertible and xDrive Convertible), 2021-2023 4 Series (Coupe), 2021-2024 3 Series, 2021-2023 X4, 2021-2024 X3 vehicles. Please see the recall report for a complete list of all models. The engine starter may overheat and catch fire due to wear on an internal component.

Risk: Fire increases the risk of injury.

Remedy: Dealers will replace the engine starter, free of charge. Owner notification letters were mailed July 21, 2026. Owners may contact BMW customer service at 1-800-525-7417 or Toyota's customer service at 1-800-331-4331. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning March 24, 2026.

NHTSA's record and documents

Electrical system: starter assembly

NHTSA campaign 25V636000 · reported Sep 23, 2025 · 199,674 vehicles potentially affected

Park outside

BMW of North America, LLC (BMW) is recalling certain 2019-2021 BMW 330i, 2019-2022 BMW Z4, 2020-2022 BMW 530i, X3, X4, Toyota Supra, 2021-2022 BMW 430i, 430i Convertible, and 2022 BMW 230i vehicles. The engine starter relay may corrode, causing the relay to overheat and short circuit.

Risk: A short circuit in the starter relay may increase the risk of a fire.

Remedy: Owners are advised to park their vehicles outside and away from structures until the remedy is complete. Dealers will replace the engine starter, free of charge. Owner notification letters were mailed February 6, 2026. Owners may contact BMW customer service at 1-800-525-7417. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov November 14, 2025.

NHTSA's record and documents

Electrical system: software; Seat belts

NHTSA campaign 23V584000 · reported Aug 16, 2023 · 144 vehicles potentially affected

BMW of North America, LLC (BMW) is recalling certain 2019-2022 330i, 330i xDrive, M340i, 2022 430i Coupe, 2021-2022 430i, M440i Convertible, and 2020-2022 228i xDrive Gran Coupe vehicles. The receiver audio module control unit software may fail to properly generate audible seat belt warnings to the driver to fasten their seat belt. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."

Risk: An audible chime that does not properly alert the driver to fasten their seat belt increases the risk of injury in a crash.

Remedy: Dealers will update the receiver audio module software, free of charge. Owner notification letters were mailed October 12, 2023. Owners may contact BMW customer service at 1-800-525-7417.

NHTSA's record and documents

Seat belts

NHTSA campaign 21V554000 · reported Jul 21, 2021 · 21,537 vehicles potentially affected

BMW of North America, LLC (BMW) is recalling certain 2021 2 Series (230i, 230i xDrive, M240i, M240i xDrive), 330e, 330e Xdrive, 4 Series Coupe (430i, 430i xDrive, M440i xDrive) M4 Coupe, M4 Competition Coupe, BMW 4 Series Convertible (430i, M440i), BMW X1 sDrive28i, xDrive28i, 2 Series Gran Coupe (228i, 228i xDrive, M235i xDrive), M2 Competition Coupe, 330i, 330i xDrive, M340i, M340i xDrive, M3, M3 Competition, 530i, 530i xDrive, 540i, 540i xDrive, MINI Hardtop 2 Door (Cooper, CooperS, JCW), X2 sDrive28i, X2 xDrive28i, X2 M35i, Z4 sDrive30i, Z4 M40i, MINI Hardtop 2 Door (Cooper SE), MINI Convertible (Cooper, Cooper S, JCW), MINI Clubman (Cooper S, Cooper S All4, JCW), MINI Countryman (Cooper, Cooper All4, Cooper S, Cooper S All4, JCW All4), Rolls Royce Ghost, MINI Countryman (Cooper S E All4), Rolls Royce Phantom, Rolls Royce Cullinan, and Toyota Supra vehicles. The passenger seat belt Automatic Locking Retractor (ALR) may deactivate early, before the webbing fully retracts. As such, these assemblies fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."

Risk: During a crash, a seat belt retractor that does not function as intended increases the risk of injury.

Remedy: Dealers will inspect the seat belt retractors (including the seat belts) and, if necessary, replace the retractors, free of charge. Owner notification letters were mailed on September 3, 2021. Owners may contact BMW customer service at 1-800-525-7417; 1-866-825-1525 (MINI); 1-877-877-3735 (Rolls Royce); and 1-888-270-9371 (Toyota).

NHTSA's record and documents

Air bags: side/window; Air bags: side/window

NHTSA campaign 21V176000 · reported Mar 15, 2021 · 1,850 vehicles potentially affected

BMW of North America, LLC (BMW) is recalling certain 2021 430i and M440i 4 Series Convertible vehicles. In certain side-impact crashes, the head-thorax air bag may not deploy as intended.

Risk: An air bag that deploys incorrectly can increase the risk of injury in a crash.

Remedy: Dealers will update the software, at no charge. All affected vehicles are still in dealer inventory, and therefore no owner letters will be mailed. The recall began March 9, 2021. Owners may contact BMW customer service at 1-800-525-7417.

NHTSA's record and documents

Back over prevention: sensing system; Back over prevention: software

NHTSA campaign 21V096000 · reported Feb 19, 2021 · 13,858 vehicles potentially affected

BMW of North America, LLC (BMW) is recalling certain 2019-2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, X4 xDrive30i, X4 M40i, M550i, X4M, X5 sDrive40i, X5 xDrive40i, X5 xDrive50i, X5M, X5 M50i, X7 xDrive40i, X7 xDrive50i, X7 M50i, Alpina XB7, 330i, 330i xDrive, M340i, M340i xDrive, and 8 Series Coupe, Convertible and Grand Coupe, 840i, 840i xDrive, M850i xDrive, M8, 2020-2021 530e, 530e xDrive, 330e, 330e xDrive, 745Le, 745Le xDrive, X5 xDrive45e, X3 xDrive30e, X6 sDrive40i, X6 xDrive40i, X6 xDrive50i, X6 M50i, X6M, 530i, 530i xDrive, 540i, 540i xDrive, M550i xDrive, M5, 740i, 740Li, 740Li xDrive, M760i Drive, M760Li xDrive, 750Li xDrive Alpina, Alpina B7 xDrive, and 2021 4 Series Coupe 430i, 430i xDrive, M440i xDrive vehicles. When shifting into Reverse, a small portion of the rearview image may be obscured, or the screen may not illuminate. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 111, "Rear Visibility."

Risk: If the driver relies on only the rearview camera image, the missing or reduced rearview image view can increase the risk of a crash or injury.

Remedy: BMW will notify owners, and dealers will inspect the rearview camera software and update it if necessary, free of charge. The recall began April 16, 2021. Owners may contact BMW customer service at 1-800-525-7417.

NHTSA's record and documents

Electrical system: 12v/24v/48v battery

NHTSA campaign 20V761000 · reported Dec 9, 2020 · 812 vehicles potentially affected

BMW of North America, LLC (BMW) is recalling certain 2021 M340i xDrive, M440i xDrive Coupe, 530i, 530i xDrive, 540i, 540i xDrive, 740Li, 740Li xDrive, 840i Gran Coupe, 840i xDrive Gran Coupe, X5 sDrive40i, X5 xDrive40i, X6 sDrive40i, X6 xDrive40i, and X7 xDrive40i vehicles. The connection between the 48-Volt battery and the starter-generator may not have been assembled properly, which can cause increased electrical resistance at the connections.

Risk: Increased electrical resistance can increase the risk of a fire.

Remedy: BMW will notify owners, and dealers will inspect the connection between the 48-Volt battery and the starter-generator assembly, replacing it if necessary, free of charge. The recall is expected to begin April 12, 2021. Owners may contact BMW customer service at 1-800-525-7417.

NHTSA's record and documents

Service bulletins and investigations

Carmakers sent NHTSA 137 service bulletins and notices that cover the 2021 4 Series, the latest on May 6, 2026. They tell dealers how to fix known issues.

The parts they mention most: equipment (55), electrical system (52), structure (12), engine and engine cooling (9), exterior lighting (8).

NHTSA defect investigations

Opening an investigation isn't a finding of a defect. Outcomes are as NHTSA's summary states them. A recall is shown as an investigation's outcome only where NHTSA's summary names it; other recalls NHTSA's file lists with it are marked as listed, not caused.

InvestigationPartOpenedStatus
Defect petition DP22005
Pedestrian alert sounds · covers 43 makes
Electrical systemJan 27, 2023Closed Aug 7, 2023
Petition withdrawn
NHTSA's record and documents

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 4 Series.

Oil change near you: Jiffy Lube · Take 5

Specs

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

VersionEngineTransmissionFuelCity / hwy / comb
430i
Rear-Wheel Drive
2.0 L, 4 cyl, turboAutomatic (S8)Premium Gasoline26 / 34 / 29
430i
Rear-Wheel Drive
2.0 L, 4 cyl, turboAutomatic (S8)Premium Gasoline24 / 33 / 27
430i xDrive
All-Wheel Drive
2.0 L, 4 cyl, turboAutomatic (S8)Premium Gasoline24 / 33 / 27
M440i
Rear-Wheel Drive
3.0 L, 6 cyl, turboAutomatic (S8)Premium Gasoline23 / 31 / 26

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