2021 BMW X4 — Full Specifications
As an Amazon Associate and CJ Affiliate and AWIN publisher we earn from qualifying purchases. Links below are affiliate links.
Running gear matters most — before anything else, UK: check tyre prices at TirendoUS: check wheel & tyre prices at WheelHero for this car's fitment.
The 2021 BMW X4 is an SUV offered with 2 engines (2L 4-cyl turbo, 3L 6-cyl turbo). Its most fuel-efficient configuration returns around 30 mpg (UK) / 25 mpg (US EPA) combined, with 19–30 mpg (UK) across all configurations. Owners often keep a BMW X4 workshop manual to hand for servicing and repairs.
Compared with the 2020 BMW X4: Fuel economy is essentially unchanged at around 30 mpg (UK) combined. The engine line-up listed by EPA is unchanged.
Full Specifications
| Engine (most efficient) | 2L 4-cyl turbo |
|---|---|
| Engine options | 2L 4-cyl turbo · 3L 6-cyl turbo |
| Transmission (most efficient) | Automatic (S8) |
| Fuel Type | Premium Gasoline |
| Powertrain | Conventional |
| Drive | All-Wheel Drive |
| Body Style | SUV |
| Fuel Economy (UK) | 30 combined / 28 urban / 35 extra-urban mpg |
| Fuel Economy (US EPA) | 25 combined / 23 city / 29 highway mpg |
| CO₂ Emissions | 218 g/km |
| EPA Greenhouse Gas Score | 2 / 10 (10 = lowest emissions) |
| EPA Est. Annual Fuel Cost | $3,300 (15,000 mi/yr, US prices) |
Engine & Transmission Options
EPA lists 2 configurations for the 2021 BMW X4 across 2 engines (2L 4-cyl turbo, 3L 6-cyl turbo). Combined fuel economy ranges from 16 to 25 mpg (US), or 19 to 30 mpg (UK), depending on engine, transmission and drive. The headline figures at the top of this page describe the most fuel-efficient configuration.
| Engine | Transmission | Drive | MPG (UK) | MPG (US) | CO₂ g/km | Fuel cost / yr |
|---|---|---|---|---|---|---|
| 2L 4-cyl turbo | Automatic (S8) | All-Wheel Drive | 30 | 25 (23/29) | 218 | $3,300 |
| 3L 6-cyl turbo | Automatic (S8) | All-Wheel Drive | 19 | 16 (14/19) | 339 | $5,150 |
MPG (US) shows combined, with city/highway in brackets. Highlighted row = the configuration used for the headline figures. Source: US EPA fueleconomy.gov.
Owner Essentials for the 2021 BMW X4
Running Costs: 2021 BMW X4
Covering around 8,000 miles a year in a 2021 BMW X4 at 30 mpg combined, expect roughly 1,212 litres of fuel annually — multiply by your local price per litre for a cost estimate. For US owners, the EPA estimates about $3,300 a year in fuel for the most efficient configuration (15,000 miles, national average prices). Work out exact fuel costs with the fuel cost calculator on 247Calculators.
Convert between MPG and L/100km with the unit converters on 247QuickTools. Not sure what tyre size fits? 247TyreCheck explains tyre sizing.
Planning a road trip? Grab a road trip packing list. Only need this car occasionally? See our buy vs rent comparison.
2021 BMW X4 Safety Ratings (NHTSA)
No NHTSA crash-test rating is on record for this model year. The NHTSA rates only a subset of vehicles each year; you can browse every rated vehicle on our NHTSA Safety Ratings hub.
Recalls & Owner Complaints (NHTSA)
NHTSA lists 7 safety recall campaigns that include the 2021 BMW X4 (as of 6 October 2026). Most affected areas: Electrical system (2), Back over prevention (2), Seats (1). 1 campaign carried a “do not drive” or “park outside” advisory. A campaign often covers several model years or models, so check your own VIN to see whether your car is affected.
- Electrical system — campaign 26V056000, reported 30 January 2026. Risk: Fire increases the risk of injury.
- Electrical system — campaign 25V636000, reported 23 September 2025. Risk: A short circuit in the starter relay may increase the risk of a fire.
- Seats — campaign 23V211000, reported 29 March 2023. Risk: An improperly welded seat frame may not properly restrain the occupant during a crash, increasing the risk of injury.
- Engine — campaign 21V598000, reported 2 August 2021. Risk: Loss of braking assist can increase the risk of a crash.
Showing the 4 most recent of 7 campaigns.
Owners have filed 6 complaints with NHTSA about the 2021 BMW X4. The most-reported areas are Engine (2), Seat belts (2), Power train (1).
Used-buyer checklist for the 2021 BMW X4
Based on where NHTSA recalls and owner complaints cluster for this model year, these are the areas worth checking before you buy:
- Electrical system (2 recall campaigns) — Test every switch, window, light and warning lamp on a test drive, and ask about battery or alternator replacements.
- Engine (1 recall campaign · 2 owner complaints) — Listen for unusual noise on a cold start, check for warning lights and ask for the service records.
- Seats (1 recall campaign) — Check seat adjusters, head restraints and seat-mounted sensors work, and confirm seat recalls were completed.
- Seat belts (2 owner complaints) — Check every belt latches and retracts properly and that any restraint recalls were completed.
Source: US NHTSA recall and consumer-complaint databases, retrieved 6 October 2026. Complaints are unverified owner reports, not confirmed defects. Check any vehicle by VIN at nhtsa.gov/recalls, and see our guide to checking a used car for recalls.
How It Compares
How does the BMW X4 compare to similar SUVs? For context, SUVs in our database average around 27 mpg (UK) combined — this model's 30 mpg figure is 3 mpg better than that average. Its 218 g/km CO₂ figure is 35 g/km lower than the 253 g/km average for SUVs on this site. This comparison is based on 1824 SUVs in our dataset.
BMW models in our database average about 28 mpg (UK) combined on their most efficient configuration; the 2021 BMW X4's 30 mpg is 2 mpg above that make average. Its 218 g/km CO₂ figure is 22 g/km lower than the 240 g/km BMW average.
Of the 11 BMW X4 model years we cover, the 2021 is the most economical on its best configuration (30 mpg UK combined). See every BMW X4 year side by side.
Last updated: · Data: US EPA (fueleconomy.gov) and NHTSA safety ratings 18 July 2026; NHTSA recalls and complaints 6 October 2026; Wikidata & curated EU catalogue 18 July 2026; European generation and engine data from Wikipedia 7 October 2026
Vehicle data sourced from manufacturer specifications. Always verify with your vehicle handbook or a qualified mechanic. This is a reference tool, not professional advice.
Recommended Accessories for the 2021 BMW X4
Frequently Asked Questions
What engine does the 2021 BMW X4 have?
EPA lists 2 engines for the 2021 BMW X4: 2L 4-cyl turbo, 3L 6-cyl turbo. The most fuel-efficient configuration pairs the 2L 4-cyl turbo with a automatic (s8).
What is the fuel economy of the 2021 BMW X4?
The most efficient configuration returns around 30 mpg (UK) combined, or 25 mpg on the US EPA cycle. Across all configurations the UK combined figure runs from 19 to 30 mpg.
How much does the 2021 BMW X4 cost to fuel per year?
The US EPA estimates about $3,300 a year in fuel for the most efficient configuration, based on 15,000 miles of mixed driving and national average fuel prices. Your own cost will depend on mileage and local prices.
Does the 2021 BMW X4 have any recalls?
NHTSA lists 7 safety recall campaigns that include the 2021 BMW X4 (as of 6 October 2026). Most affected areas: Electrical system (2), Back over prevention (2), Seats (1). 1 campaign carried a “do not drive” or “park outside” advisory. A campaign often covers several model years or models, so check your own VIN to see whether your car is affected.
What are the most common problems reported for the 2021 BMW X4?
Among the 6 owner complaints filed with NHTSA, the most-reported areas are Engine (2 complaints), Seat belts (2 complaints), Power train (1 complaint). Complaints are unverified owner reports, not confirmed defects, and raw counts rise with how many cars were sold.
Is the BMW X4's fuel economy good for an SUV?
Yes — it returns around 30 mpg (UK) combined, against a same-body-style average of roughly 27 mpg among the SUVs we track, making it one of the more efficient options in its class.