EPA ratings · 2021 · BMW · X3
2021 BMW X3 Fuel Economy
EPA rates the 2021 BMW X3's 6 trims from 16 to 27 MPG combined, X3 M to X3 sDrive30i. Electric and plug-in trims show MPGe and kWh per 100 miles. The table below prices every trim per mile at a fuel price and mileage you can change.
EPA ratings by trim
| Trim | Engine | Transmission | Drive | City | Hwy | Combined | kWh/100 mi | Electric range |
|---|---|---|---|---|---|---|---|---|
| X3 M · Premium | 3 L, 6 cyl | Automatic (S8) | All-Wheel Drive | 14 | 19 | 16 MPG | — | — |
| X3 M Competition · Premium | 3 L, 6 cyl | Automatic (S8) | All-Wheel Drive | 14 | 19 | 16 MPG | — | — |
| X3 M40i · Premium | 3 L, 6 cyl | Automatic (S8) | All-Wheel Drive | 21 | 27 | 23 MPG | — | — |
| X3 sDrive30i · Premium | 2 L, 4 cyl | Automatic (S8) | Rear-Wheel Drive | 25 | 29 | 27 MPG | — | — |
| X3 xDrive30e · Premium and Electricity | 2 L, 4 cyl, Plug-in Hybrid | Automatic (S8) | All-Wheel Drive | 21 | 27 | 24 MPG | 56.0 | 18 mi |
| X3 xDrive30i · Premium | 2 L, 4 cyl | Automatic (S8) | All-Wheel Drive | 23 | 29 | 25 MPG | — | — |
City and highway are EPA's adjusted label figures; combined is the 55/45 blend printed on the window sticker. For electric and plug-in trims the MPG columns are MPGe, and the kWh per 100 miles is the figure a charging cost actually turns on; EPA measures it at the wall, so charging losses are already in it. Unrounded combined figures, where EPA publishes them: X3 M 16.1587; X3 M Competition 16.1587; X3 M40i 23.1538; X3 sDrive30i 26.574; X3 xDrive30e 23.7073; X3 xDrive30i 25.2654.
What the rating costs per mile
The rating divided by a price, times your miles. It starts at EIA's current U.S. averages and EPA's 15,000 miles so the right-hand column is comparable; type your own pump price, home rate and mileage over them.
| Trim | Runs on | Rated | Per mile | Per year | EPA's figure |
|---|---|---|---|---|---|
| X3 M | Premium Gasoline | 16 MPG | 26.8¢ | $4,016 | $5,150 |
| X3 M Competition | Premium Gasoline | 16 MPG | 26.8¢ | $4,016 | $5,150 |
| X3 M40i | Premium Gasoline | 23 MPG | 18.6¢ | $2,794 | $3,550 |
| X3 sDrive30i | Premium Gasoline | 27 MPG | 15.9¢ | $2,380 | $3,050 |
| X3 xDrive30e — on gasoline | Premium Gasoline | 24 MPG | 17.8¢ | $2,678 | $3,400 |
| X3 xDrive30e — on electricity | Electricity | 56 kWh/100 mi | 10.2¢ | $1,525 | — |
| X3 xDrive30i | Premium Gasoline | 25 MPG | 17.1¢ | $2,570 | $3,300 |
Per mile = price ÷ rated MPG (gasoline) or price per kWh × kWh per 100 miles ÷ 100 (electricity). Per year = per mile × miles. EPA's figure is its own annual fuel cost at 15,000 miles, 55% city, and the national price in force when the file was built; it will differ from the middle columns whenever the price here differs. A plug-in hybrid is shown once on each fuel; its real cost sits between them, by how much of its driving is on the battery.
Fuel only — before depreciation, insurance, maintenance or tires, which the True Cost per Mile Calculator adds. Most drivers land below the rating; the True MPG Calculator measures your own from two fill-ups. The EV vs. Gas Cost Calculator sets the electric trim against a gasoline one over a year.
EPA's own figures, and why they differ
The “EPA's figure” column is EPA's annual fuel cost from the same file: 15,000 miles, 55% city, and the national fuel price fueleconomy.gov was using on the day the file was built (2026-09-29). fueleconomy.gov recomputes its page every week at the current price, so its number and the file's drift apart between file dates; the middle columns here use a price you can see and change, which is the only honest way to compare two cars. EPA also prints a five-year “you save/spend” against the average new vehicle (spends $3,250 for the X3 sDrive30i); it rests on the same assumptions and is not repeated here as a result.
Every figure on this page is a rating, not a measurement of any particular car. The site never calls a rating wrong; it shows what your own price and miles do to it. See the model on fueleconomy.gov.
Other model years of the BMW X3: 2026, 2025, 2024, 2023, 2022, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004.
Related tools
Price the same miles on gasoline and on electricity, using your fuel price, your utility rate, and each car's rated efficiency.
Open tool →True MPG CalculatorYour car's real fuel economy from two odometer readings and a fill-up — and how far it falls from its EPA rating.
Open tool →Commute Cost CalculatorWhat getting to work costs per day, per month, and per year — energy only, or all-in at the IRS standard mileage rate.
Open tool →Gas Prices by Region and StateThis week's average price of regular gasoline for the U.S., every state and ten cities, from EIA's weekly survey — a dated figure to start from, never one assumed for you.
Open tool →Electricity Prices by StateThe average residential price of electricity in every state, by month, from EIA's utility filings — and what each rate does to a mile in an electric car.
Open tool →Informational only — published averages for scale and comparison, not a quote for any pump, utility or vehicle. Your own price is the one that counts, and every calculator on this site takes it as an input.
Ratings: U.S. EPA and U.S. DOE, fueleconomy.gov vehicles.csv dated 2026-09-29 (EPA record ids 42597, 42598, 42900, 42849, 43740, 42899). Prices: EIA, U.S. regular gasoline week of October 19, 2026; U.S. residential electricity August 2026. Snapshots refreshed monthly.