Porsche 911 (991/2) Real MPG: what owners actually get
The official figure is what a Porsche 911 (991/2) managed in a laboratory. These are the figures owners report from the road, engine by engine, for every generation we hold. Add your own at the bottom and the averages get better for the next buyer.
28.1mpg
Real-world average, all engines
98%
of the official combined figure
22–35
Range reported by owners (mpg)
13
Owner submissions
Porsche 911 (991/2)
2015–2018 · real average 28.1 mpg · owners report 22.0–35.0 mpg · 13 submissions
Engine
Official (NEDC)
Official (WLTP)
Real MPG
% of official
Owners report
Carerra 4 Cabriolet GTS
29.1
–
–
–
–
Carerra 4 Cabriolet GTS PDK
31.0
–
–
–
–
Carrera
34.0
–
29.9
88%
–
Carrera 4
32.5
–
–
–
–
Carrera 4 Cabriolet
31.7
–
–
–
–
Carrera 4 Cabriolet PDK
35.8
–
–
–
–
Carrera 4 GTS
29.7
–
–
–
–
Carrera 4 GTS PDK
31.7
–
–
–
–
Carrera 4 PDK
36.7
–
–
–
–
Carrera 4S
31.7
–
–
–
–
Carrera 4S Cabriolet
31.4
–
–
–
–
Carrera 4S Cabriolet PDK
35.3
–
–
–
–
Carrera 4S PDK
35.8
–
–
–
–
Carrera 4S PDK Cabriolet
–
25.0–25.7
–
–
–
Carrera Cabriolet GTS PDK
33.6
–
–
–
–
Carrera Cabriolet PDK
37.7
–
–
–
–
Carrera Cabriolet S PDK
30.1
–
–
–
–
Carrera GTS
30.1
–
–
–
–
Carrera GTS PDK
34.0
–
–
–
–
Carrera PDK
38.2
–
–
–
–
Carrera S
32.5
–
–
–
–
Carrera S Cabriolet
32.1
–
–
–
–
Carrera S Cabriolet PDK
36.2
–
–
–
–
Carrera S PDK
36.7
27.2
26.5
97%*
–
Carrera S PDK Cabriolet
–
26.4
–
–
–
Carrera T
29.7
–
–
–
–
Carrera T PDK
33.2
–
–
–
–
GT2 RS
23.9
–
–
–
–
GT3
22.2
–
–
–
–
GT3 R
21.2
–
–
–
–
GT3 RS
22.1
–
22.1
100%
–
Speedster
–
20.6
–
–
–
Targa 4
31.7
–
–
–
–
Targa 4 GTS
29.1
–
–
–
–
Targa 4 GTS PDK
31.0
–
–
–
–
Targa 4 PDK
35.8
–
–
–
–
Targa 4S
31.4
–
–
–
–
Targa 4S PDK
35.3
–
–
–
–
Turbo Cabriolet PDK
28.5
–
–
–
–
Turbo PDK
29.1
–
–
–
–
Turbo S Cabriolet PDK
28.5
–
–
–
–
Turbo S PDK
29.1–31.0
–
32.1
107%
–
All figures in miles per gallon (UK). “Owners report” is the spread of individual submissions for that engine. * Measured against the WLTP figure rather than NEDC.
Add your Porsche 911 (991/2) Real MPG
What does yours actually do? Read it off the trip computer over a full tank or work it out from litres and miles. No postcode, no sign-up. The more people add, the better the averages get, and this page stays free.
Porsche 911 (991/2) fuel economy questions
What is the real-world MPG of a Porsche 911 (991/2)?
Owners report an average of 28.1 mpg across all Porsche 911 (991/2) engines with data, about 98% of the official combined figure. The engine tables on this page give the figure for each engine and generation.
Why is the Porsche 911 (991/2) real MPG lower than the official figure?
Official figures come from a laboratory test cycle, not the road. Cold starts, short trips, hills, load, tyres and driving style all cost fuel the test does not see. A gap of 10 to 30 per cent is normal; a much bigger gap on one engine usually points at a fault, a heavy right foot, or a diesel that never gets warm.
Where did the Honest John Porsche 911 (991/2) Real MPG page go?
Honest John closed in August 2026 and its Real MPG section went with it. This page is where the Porsche 911 (991/2) figures now live: rebuilt from the archived Honest John dataset, with the official figures kept alongside, and reopened for new submissions. CarAdCheck is not affiliated with Honest John or Volkswagen Financial Services.
Where the Porsche 911 (991/2) figures come from
If you used the Honest John Real MPG section before the site closed in 2026, this is where the Porsche 911 (991/2) figures now live. The owner-reported averages above were rebuilt from the archived Honest John dataset (archived page, 2026-08) alongside the official NEDC and WLTP figures and new submissions from CarAdCheck readers, and the section is open so they keep improving. Real-world figures also feed the running-cost estimate in our free advert check.
CarAdCheck is not affiliated with Honest John or Volkswagen Financial Services. How we rebuilt Real MPG.