Buick Century
21 MPG The 2005 Buick Century is EPA-rated at 21 MPG combined (18 city / 27 highway). Over 15,000 miles a year that is about 714 gallons, $2286 a year in fuel, or $0.152 per mile at $3.20/gal.
Across its full 1984–2005 run it averages 21.1 MPG, falling by 0.7 MPG over 21 model years.
Running cost at different fuel prices and mileages
The figure everyone actually wants, and the one the EPA does not publish — because it depends on a fuel price no agency will commit to.
| Fuel price | Per mile | 10,000 mi/yr | 15,000 mi/yr | 20,000 mi/yr |
|---|---|---|---|---|
| $2.50/gal | $0.119 | $1190 | $1786 | $2381 |
| $3.00/gal | $0.143 | $1429 | $2143 | $2857 |
| $3.20/gal | $0.152 | $1524 | $2286 | $3048 |
| $3.50/gal | $0.167 | $1667 | $2500 | $3333 |
| $4.00/gal | $0.190 | $1905 | $2857 | $3810 |
| $4.50/gal | $0.214 | $2143 | $3214 | $4286 |
| $5.00/gal | $0.238 | $2381 | $3571 | $4762 |
Every model year
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 2005 | 21 MPG | 18 | 27 | $2950 | 423 | 1 |
| 2004 | 21 MPG | 18 | 27 | $2950 | 423 | 1 |
| 2003 | 21 MPG | 18 | 26 | $2950 | 423 | 1 |
| 2002 | 21 MPG | 18 | 26 | $2950 | 423 | 1 |
| 2001 | 21 MPG | 18 | 26 | $2950 | 423 | 1 |
| 2000 | 21 MPG | 18 | 27 | $2950 | 423 | 1 |
| 1999 | 21 MPG | 17 | 26 | $2950 | 423 | 1 |
| 1998 | 21 MPG | 17 | 27 | $2950 | 423 | 1 |
| 1996 | 22.5 MPG | 19.5 | 27.5 | $2775 | 397 | 2 |
| 1995 | 20 MPG | 17 | 26 | $3100 | 444 | 2 |
| 1994 | 22 MPG | 19.5 | 27 | $2850 | 407 | 2 |
| 1993 | 21 MPG | 18.7 | 26 | $2983 | 426 | 3 |
| 1992 | 20.3 MPG | 17.7 | 26.3 | $3083 | 439 | 3 |
| 1991 | 20.3 MPG | 17.7 | 26.3 | $3083 | 439 | 3 |
| 1990 | 21.3 MPG | 18.7 | 26.7 | $2917 | 418 | 3 |
| 1989 | 21 MPG | 18.6 | 26 | $2960 | 424 | 5 |
| 1988 | 21.3 MPG | 18.5 | 26.5 | $2938 | 421 | 4 |
| 1987 | 20.8 MPG | 17.8 | 26 | $3013 | 430 | 4 |
| 1986 | 20.5 MPG | 17.8 | 26.3 | $3050 | 436 | 4 |
| 1985 | 21.4 MPG | 18.3 | 26.1 | $3144 | 438 | 8 |
| 1984 | 21.7 MPG | 18.7 | 26.6 | $3133 | 434 | 9 |
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.
How it compares in its class
Among the 261 midsize cars models tracked here, the Buick Century ranks 167 on current figures, against a class average of 27.2 MPG.
Closest more-efficient alternatives in the same class: Buick Lacrosse/Allure (21.3), Chevrolet Celebrity (21.3), Chrysler Sebring 4 Door (21.3), Dodge 600 (21.3), Dodge Stratus 4 Door (21.3).
Tailpipe CO₂ is rated at 423 grams per mile, which works out to roughly 6.3 tonnes a year at 15,000 miles.
Questions
What MPG does the Buick Century get?
The 2005 Buick Century is rated at 21 MPG combined by the EPA — 18 city and 27 highway. Across all 21 model years in the database it averages 21.1 MPG, ranging from 18 to 27 depending on year and trim.
How much does a Buick Century cost in fuel per year?
At 21 MPG and 15,000 miles a year, it burns about 714 gallons — roughly $2286 a year with fuel at $3.20 a gallon, or $0.152 per mile. The EPA's own published annual figure for the 2005 model is $2950.
Has the Buick Century become more efficient over time?
No — it has actually gone backwards, from 21.7 MPG in 1984 to 21 in 2005. That usually reflects the model growing heavier, more powerful, or moving upmarket rather than the engineering getting worse.
Is the Buick Century efficient for its class?
It ranks 167 of 261 in the Midsize Cars class on current figures, against a class average of 27.2 MPG. That is 6.2 worse than typical for the class.
EPA test figures from fueleconomy.gov. Cost per mile and annual fuel spend are computed at a reference price of $3.20 per gallon — use your own price. Estimates based on official test figures and average fuel prices. Real-world consumption varies with driving style, load, terrain and maintenance.