Mazda 6
What it costs to keep fuelled
$1,745a year, fuel only
The 2021 Mazda 6 is EPA-rated at 27.5 MPG combined (24.5 city / 33 highway). Over 15,000 miles a year that is about 545 gallons, $1745 a year in fuel, or $0.116 per mile at $3.20/gal.
Across its full 2003–2021 run it averages 24.9 MPG, improving by 6 MPG over 19 model years.
The band is how far one gallon carries it: 27.5 of the 60 MPG this scale runs to. The square tick is the midsize cars average, 27.2.
- Fuel, per year
- $1,745 at 15,000 mi
- Per mile
- $0.116
- Per kilometre
- $0.072
- Gallons burned/yr
- 545
1 mile = 1.609344 km · fuel at $3.20/gal, fixed JUL 2026
Test figure — not a road resultSOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
How this is worked out
- Start from the EPA combined figure for the model year — a laboratory test cycle run to a fixed procedure, not a road result. Where a year sold several engines or drivetrains, the trims are averaged and the trim count is printed beside the row so you can see how much averaging is behind it.
- Fix a pump price. This site keeps one reference price, $3.20 a US gallon, fixed JUL 2026 and printed next to every dollar figure it produces. It is an assumption with a date on it, not a quote — put your own price in.
- Fix an annual distance. Every annual figure on this site uses 15,000 miles a year, roughly the US average. A cost per year with no stated distance is not a number, it is a mood.
- Divide distance by economy for gallons, multiply by price for the year's fuel, divide price by economy for one mile. The per-kilometre line is that last figure divided by 1.609344 — the same money, in the unit most of the world drives in.
- Stop there. No depreciation, no tyres, no insurance, no servicing. This is the fuel line of the ledger and it is labelled as one; depreciation usually dwarfs everything on it.
gallons/yr = miles/yr ÷ MPG fuel $/yr = gallons/yr × $/gal cost $/mi = $/gal ÷ MPG cost $/km = cost $/mi ÷ 1.609344
The full method, the licence note, and what a test figure cannot tell you →
Re-run the ledger at another pump price
Every line above rests on one pump price. Here is the same entry re-costed at six others, because the price is the part that changes while the test sheet stays put.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.091 | $909 | $1364 | $1818 |
| $3.00/gal | $0.109 | $1091 | $1636 | $2182 |
| $3.20/gal | $0.116 | $1164 | $1745 | $2327 |
| $3.50/gal | $0.127 | $1273 | $1909 | $2545 |
| $4.00/gal | $0.145 | $1455 | $2182 | $2909 |
| $4.50/gal | $0.164 | $1636 | $2455 | $3273 |
| $5.00/gal | $0.182 | $1818 | $2727 | $3636 |
SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
The whole service history, sheet by sheet
19 model years on file. Read down the combined column: a nameplate that got heavier shows it here long before any brochure admits it.
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 2021 | 27.5 MPG | 24.5 | 33 | $2275 | 319 | 2 |
| 2020 | 27.5 MPG | 24.5 | 33 | $2275 | 319 | 2 |
| 2019 | 27.3 MPG | 24.3 | 33 | $2283 | 322 | 3 |
| 2018 | 27.3 MPG | 24.3 | 33 | $2283 | 322 | 3 |
| 2017 | 29 MPG | 25.7 | 34.7 | $2150 | 306 | 3 |
| 2016 | 30.3 MPG | 26.3 | 37 | $2067 | 294 | 3 |
| 2015 | 30.3 MPG | 26.3 | 37 | $2067 | 295 | 3 |
| 2014 | 30.3 MPG | 26.3 | 37.3 | $2067 | 293 | 3 |
| 2013 | 23 MPG | 20 | 29 | $2717 | 398 | 3 |
| 2012 | 23.3 MPG | 20.3 | 29 | $2683 | 383 | 3 |
| 2011 | 23.3 MPG | 20.3 | 29 | $2683 | 383 | 3 |
| 2010 | 22.3 MPG | 19.3 | 28 | $2800 | 400 | 3 |
| 2009 | 22.3 MPG | 19.3 | 28 | $2800 | 400 | 3 |
| 2008 | 22 MPG | 19.3 | 26.8 | $2850 | 407 | 4 |
| 2007 | 21.2 MPG | 18.6 | 26 | $3110 | 423 | 5 |
| 2006 | 21.2 MPG | 18.6 | 26 | $3110 | 423 | 5 |
| 2005 | 21.3 MPG | 18.8 | 25.8 | $2938 | 420 | 4 |
| 2004 | 21.3 MPG | 18.8 | 25.8 | $2963 | 422 | 4 |
| 2003 | 21.5 MPG | 19 | 26.3 | $2913 | 416 | 4 |
Where a model year offered several engines or drivetrains, the figure is the average across all EPA-tested trims that year — the trim count is shown so you can see how much averaging is involved.
SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
Marked against the rest of the midsize cars bay
Among the 261 midsize cars models tracked here, the Mazda 6 ranks 75 on current figures, against a class average of 27.2 MPG — the square tick on the gauge above.
Closest more-efficient alternatives in the same class: Acura RLX Hybrid (28), Audi A6 (28), BMW 530i (28), BMW 540i xDrive Sedan (28), BMW X2 xDrive28i (28).
Tailpipe CO₂ is rated at 319 grams per mile, which works out to roughly 4.8 tonnes a year at 15,000 miles.
Questions asked across the counter
What MPG does the Mazda 6 get?
The 2021 Mazda 6 is rated at 27.5 MPG combined by the EPA — 24.5 city and 33 highway. Across all 19 model years in the database it averages 24.9 MPG, ranging from 19 to 32 depending on year and trim.
How much does a Mazda 6 cost in fuel per year?
At 27.5 MPG and 15,000 miles a year, it burns about 545 gallons — roughly $1745 a year with fuel at $3.20 a gallon, or $0.116 per mile. The EPA's own published annual figure for the 2021 model is $2275.
Has the Mazda 6 become more efficient over time?
Yes. It has gone from 21.5 MPG in 2003 to 27.5 in 2021 — an improvement of 6 MPG, or 28% across 19 model years.
Is the Mazda 6 efficient for its class?
It ranks 75 of 261 in the Midsize Cars class on current figures, against a class average of 27.2 MPG. That is 0.3 better than typical for the class.
Pull another logbook off the same shelf
Same class, nearest economy first — the ones a buyer is genuinely choosing between.
SOURCE·US EPA fuel-economy test data·FUEL ASSUMED AT $3.20/GAL FROM JUL 2026·REVIEWED JUL 2026
Cost per mile, per kilometre and per year are computed at a reference price of $3.20 a gallon over 15,000 miles, fixed JUL 2026 — set your own pump price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.
