Porsche Cayman
23 MPG The 2020 Porsche Cayman is EPA-rated at 23 MPG combined (20.5 city / 26.5 highway). Over 15,000 miles a year that is about 652 gallons, $2087 a year in fuel, or $0.139 per mile at $3.20/gal.
Across its full 2007–2020 run it averages 23.5 MPG, improving by 1 MPG over 13 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 | $0.109 | $1087 | $1630 | $2174 |
| $3.00/gal | $0.130 | $1304 | $1957 | $2609 |
| $3.20/gal | $0.139 | $1391 | $2087 | $2783 |
| $3.50/gal | $0.152 | $1522 | $2283 | $3043 |
| $4.00/gal | $0.174 | $1739 | $2609 | $3478 |
| $4.50/gal | $0.196 | $1957 | $2935 | $3913 |
| $5.00/gal | $0.217 | $2174 | $3261 | $4348 |
Every model year
| Year | Combined | City | Highway | EPA fuel cost/yr | CO₂ g/mi | Trims |
|---|---|---|---|---|---|---|
| 2020 | 23 MPG | 20.5 | 26.5 | $3350 | 385 | 2 |
| 2019 | 24.5 MPG | 21.5 | 28.5 | $3150 | 361 | 2 |
| 2018 | 24.5 MPG | 21.5 | 28.5 | $3150 | 361 | 2 |
| 2017 | 24.5 MPG | 21.5 | 28.5 | $3150 | 361 | 2 |
| 2016 | 24.5 MPG | 21 | 30 | $3150 | 364 | 2 |
| 2015 | 24.5 MPG | 21 | 30 | $3150 | 364 | 2 |
| 2014 | 24.5 MPG | 21 | 30 | $3150 | 364 | 2 |
| 2012 | 22.5 MPG | 19.5 | 27.5 | $3425 | 395 | 2 |
| 2011 | 22.5 MPG | 19.5 | 27.5 | $3425 | 395 | 2 |
| 2010 | 23 MPG | 19.5 | 28 | $3350 | 387 | 2 |
| 2009 | 23 MPG | 19.5 | 28 | $3350 | 387 | 2 |
| 2008 | 22 MPG | 19.3 | 27.7 | $3500 | 405 | 3 |
| 2007 | 22 MPG | 19.3 | 27.7 | $3500 | 405 | 3 |
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 105 two seaters models tracked here, the Porsche Cayman ranks 22 on current figures, against a class average of 21.4 MPG.
Closest more-efficient alternatives in the same class: BMW Z4 M40i (23.5), Mercedes-Benz SLK350 (24), Toyota GR Supra (24.3), Audi TT Roadster (25), Toyota MR2 (25.5).
Tailpipe CO₂ is rated at 385 grams per mile, which works out to roughly 5.8 tonnes a year at 15,000 miles.
Questions
What MPG does the Porsche Cayman get?
The 2020 Porsche Cayman is rated at 23 MPG combined by the EPA — 20.5 city and 26.5 highway. Across all 13 model years in the database it averages 23.5 MPG, ranging from 21 to 25 depending on year and trim.
How much does a Porsche Cayman cost in fuel per year?
At 23 MPG and 15,000 miles a year, it burns about 652 gallons — roughly $2087 a year with fuel at $3.20 a gallon, or $0.139 per mile. The EPA's own published annual figure for the 2020 model is $3350.
Has the Porsche Cayman become more efficient over time?
Yes. It has gone from 22 MPG in 2007 to 23 in 2020 — an improvement of 1 MPG, or 5% across 13 model years.
Is the Porsche Cayman efficient for its class?
It ranks 22 of 105 in the Two Seaters class on current figures, against a class average of 21.4 MPG. That is 1.6 better 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.