2021 BMW X4
Trims, performance, features, fuel economy, safety and known problems — with the pros and cons against similar 2021 models.

- Class
- Small Sport Utility Vehicle 4WD
- Body styles
- M40i 4dr SUV, Xdrive30i 4dr SUV, M 4dr SUV
- Engines
- 2.0L 4-cyl turbo, 3.0L 6-cyl turbo
- Drivetrain
- All-Wheel Drive
- Fuel
- Premium Gasoline
- MPG (best)
- 25 combined · 23 city / 29 hwy
- Length
- 187.4 in
- Curb weight
- 4,147–4,599 lb
- NHTSA rating
- Not rated
- Recalls
- 7 campaigns
Pros & cons
What's good
- Few owner complaints6 complaints filed with NHTSA versus about 20 for similar models.
Watch out for
- Premium fuel requiredEvery gasoline version is rated for premium, which raises running costs.
- "Park outside" recallCheck that the recall repair was done before buying or driving.
Calculated from EPA, NHTSA and vPIC data against 34 similar 2021 models — not a review. How we calculate this →
Overview
The 2021 BMW X4 is a small SUV offered with 2 engines (2.0L 4-cyl turbo and 3.0L 6-cyl turbo) and all-wheel drive.
It measures about 187 inches long and 76 inches wide on a 113-inch wheelbase, with a curb weight of roughly 4,323 lb (M40i 4dr SUV).
EPA rates its most efficient version at 25 MPG combined (23 city / 29 highway), 5% better than the 2021 small SUV average of 23.9 MPG, for an estimated $3,300 a year in fuel.
NHTSA has not published a 5-Star overall rating for this model year.
It has 7 recall campaigns on file and owners have filed 6 complaints with NHTSA since 2015, most often about the seat belts.
What changed for 2021
No changes to engines, powertrains, drivetrains, size, EPA ratings or NHTSA crash rating compared with the 2020 X4 — a carry-over year in the data.
Compared with 2020; trim, feature and price changes aren't covered. See the 2020 X4 →
Dimensions & weight
| Body | Length | Width | Height | Wheelbase | Track F / R | Curb weight | Weight F/R |
|---|---|---|---|---|---|---|---|
| M40i 4dr SUV | 187.4 in | 75.6 in | 63.8 in | 113 in | 63.8 / 65.7 in | 4,323 lb | 50/50 |
| Xdrive30i 4dr SUV | 187.4 in | 75.6 in | 63.8 in | 113 in | 63.8 / 65.7 in | 4,147 lb | 49/51 |
| M 4dr SUV | 187.4 in | 75.6 in | 63.8 in | 113 in | 63.8 / 65.7 in | 4,599 lb | 50/50 |
Transport Canada CVS (Open Government Licence – Canada), Canadian-market figures.
Will it fit your garage? Check with your measurements →Engines, MPG & running costs
| Version | Engine | Transmission | Drive | City / Hwy / Comb | vs. class | Fuel / yr | CO₂ g/mi |
|---|---|---|---|---|---|---|---|
| X4 xDrive30i | 2.0L 4-cyl turbo | Automatic (S8) | All-Wheel Drive | 23 / 29 / 25 | +5% | $3,300 | 351 |
| X4 M40i | 3.0L 6-cyl turbo | Automatic (S8) | All-Wheel Drive | 21 / 27 / 23 | -4% | $3,550 | 379 |
| X4 M | 3.0L 6-cyl turbo | Automatic (S8) | All-Wheel Drive | 14 / 19 / 16 | -33% | $5,150 | 546 |
| X4 M Competition | 3.0L 6-cyl turbo | Automatic (S8) | All-Wheel Drive | 14 / 19 / 16 | -33% | $5,150 | 546 |
EPA estimates; "vs. class" is combined MPG against the 2021 EPA class average. How we calculate this →
Safety ratings & technology
NHTSA has not published 5-Star ratings for the 2021 BMW X4.
Similar 2021 small SUVs
| Model | Best MPG / range | NHTSA overall | Recalls |
|---|---|---|---|
| 2021 BMW X4 (this car) | 25 MPG | Not rated | 7 |
| 2021 Mercedes-Benz G-Class | 18 MPG | Not rated | 0 |
| 2021 Tesla Model Y | 326 mi | Not rated | 23 |
| 2021 Porsche Cayenne | 21 MPG | Not rated | 7 |
| 2021 BMW X5 | 23 MPG | ★★★★★ | 12 |
| 2021 Land Rover Defender | 19 MPG | Not rated | 9 |
| 2021 BMW X3 | 27 MPG | ★★★★★ | 10 |
Recalls (7)
Electrical System › Starter Assembly · Jan 30, 2026
NHTSA campaign 26V056000 · 87,394 vehicles
- Problem
- 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.
- Fix
- 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.
Electrical System › Starter Assembly › Relay · Sep 23, 2025 Park outside
NHTSA campaign 25V636000 · 199,674 vehicles
- Problem
- 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.
- Fix
- 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.
Seats · Mar 29, 2023
NHTSA campaign 23V211000 · 51 vehicles
- Problem
- BMW of North America, LLC (BMW) is recalling certain 2019-2021 330i, 330i xDrive, M340i xDrive, 2020-2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, 2021 X3 xDrive30e, X4 xDrive30i, and X4M vehicles. The seat frame may not have been welded properly to the seat rails.
- Risk
- An improperly welded seat frame may not properly restrain the occupant during a crash, increasing the risk of injury.
- Fix
- Dealers will replace the seat frame and back rest, free of charge. Owner notification letters were mailed May 22, 2023. Owners may contact BMW customer service at 1-800-525-7417.
Engine · Aug 2, 2021
NHTSA campaign 21V598000 · 50,024 vehicles
- Problem
- BMW of North America, LLC (BMW) is recalling certain 2020 M340i, M340i xDrive, 540i, 540i xDrive, X3 M40i, 2020-2021 X4 M40i, 745Le xDrive, 2019-2021 Z4 M40i, and 2020-2021 Toyota Supra vehicles. During engine start, the engine management software may cause loss of braking assist. Full mechanical braking (without assist) remains available.
- Risk
- Loss of braking assist can increase the risk of a crash.
- Fix
- Dealers will update the engine management software, free of charge. Owner notification letters were mailed on September 17, 2021. Owners may contact BMW customer service at 1-800-525-7417.
Fuel System, Gasoline › Storage › Tank Assembly · Mar 24, 2021
NHTSA campaign 21V199000 · 17 vehicles
- Problem
- BMW of North America, LLC (BMW) is recalling certain 2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, and X4, and 2021 X4 xDrive30i vehicles. The inlet check valve weld may fail, allowing the filling pipe to separate from the fuel tank.
- Risk
- Fuel may leak through the failed weld, increasing the risk of a fire.
- Fix
- BMW will notify owners, and dealers will replace the fuel tank, free of charge. The recall is scheduled to begin May 17, 2021. Owners were also contacted by telephone. To date, all repairs have been done. No further owner notification letters will be sent. Owners may contact BMW customer service at 1-800-525-7417.
Back Over Prevention › Software · Feb 19, 2021
NHTSA campaign 21V096000 · 13,858 vehicles
- Problem
- 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.
- Fix
- 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.
Back Over Prevention › Sensing System › Camera · Sep 30, 2020
NHTSA campaign 20V598000 · 312 vehicles
- Problem
- BMW of North America, LLC (BMW) is recalling certain 2020-2021 X3 sDrive 30i, X3 xDrive 30i, X3M 40i, X3 xDrive 30e, X4 xDrive 30i, X4M 40i, 530i, 540i, 540i xDrive, M550i xDrive, M5, 550e, 550e xDrive, and 550e iPerformance vehicles. A small portion of the rearview image may be slightly obscured. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."
- Risk
- If the driver relies on only the rearview camera image, the reduced rearview image view can increase the risk of a crash or injury.
- Fix
- BMW will notify owners, and dealers will inspect and, if necessary, program the rearview camera with updated software. The recall began November 18, 2020. Owners may contact BMW customer service at 1-800-525-7417.
Not every 2021 BMW X4 is affected — only a VIN check confirms your car.
Owner-reported problems
Unverified owner reports; best-sellers collect more.
Used 2021 BMW X4 buyer's checklist
- Run the VIN at nhtsa.gov/recalls. 7 recalls this year — ask for proof of repairs.
- Safety-critical recall. At least one recall carries a "Do Not Drive" or "Park Outside" warning. Do not buy until the VIN shows it was repaired.
- Seat Belts — 2 owner reports. Confirm the airbag warning light turns off after start-up and any airbag recall was completed.
- Engine — 2 owner reports. Cold-start the engine, listen for knocking, and watch for warning lights or hesitation on acceleration.
- Suspension — 1 owner reports. Drive over bumps and listen for clunks; look for uneven tire wear.
- Mileage to watch. Owners typically reported problems around 70,000 miles; ask what was repaired near that point.
- Before you pay: service records, a history report and an independent inspection.
Generated by DecodedCars from NHTSA recalls and owner complaints for the 2021 BMW X4. Not a substitute for a professional inspection.
Other X4 years
Compare all years →| Year | MPG (best) | Length | Overall | Recalls | Complaints |
|---|---|---|---|---|---|
| 2025 X4 | 24 | 187.4 in | Not rated | 1 | 4 |
| 2024 X4 | 24 | 187.4 in | Not rated | 1 | 3 |
| 2023 X4 | 24 | 187.4 in | Not rated | 2 | 8 |
| 2022 X4 | 24 | 187.4 in | Not rated | 5 | 4 |
| 2020 X4 | 25 | 187.4 in | Not rated | 10 | 15 |
| 2019 X4 | 25 | 187.4 in | Not rated | 7 | 11 |
| 2018 X4 | 23 | 183.9 in | Not rated | 1 | 11 |
| 2017 X4 | 23 | 183.9 in | Not rated | 2 | 3 |
| 2016 X4 | 23 | 183.9 in | Not rated | 2 | 10 |
| 2015 X4 | 23 | 183.9 in | Not rated | 5 | 18 |
Sources: EPA, NHTSA, Transport Canada, Wikimedia Commons. Not affiliated with NHTSA, the EPA or BMW. How we calculate this →