Real-world fuel economy

Porsche 911 (991/2) MPG: what owners actually get

Owners report 28.1 mpg from a Porsche 911 (991/2), about 98% of the official figure. On its NEDC-tested engines that is 98%, better than typical: the median NEDC-tested car in this 8,216-engine dataset returns 82%. The tables below give the figure for every engine and 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
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Porsche 911 (991/2)

2015–2018 · real average 28.1 mpg · owners report 22.0–35.0 mpg · 13 submissions

EngineOfficial (NEDC)Official (WLTP)Real MPG% of officialOwners report
Carerra 4 Cabriolet GTS29.1––––
Carerra 4 Cabriolet GTS PDK31.0––––
Carrera34.0–29.988%–
Carrera 432.5––––
Carrera 4 Cabriolet31.7––––
Carrera 4 Cabriolet PDK35.8––––
Carrera 4 GTS29.7––––
Carrera 4 GTS PDK31.7––––
Carrera 4 PDK36.7––––
Carrera 4S31.7––––
Carrera 4S Cabriolet31.4––––
Carrera 4S Cabriolet PDK35.3––––
Carrera 4S PDK35.8––––
Carrera 4S PDK Cabriolet–25.0–25.7–––
Carrera Cabriolet GTS PDK33.6––––
Carrera Cabriolet PDK37.7––––
Carrera Cabriolet S PDK30.1––––
Carrera GTS30.1––––
Carrera GTS PDK34.0––––
Carrera PDK38.2––––
Carrera S32.5––––
Carrera S Cabriolet32.1––––
Carrera S Cabriolet PDK36.2––––
Carrera S PDK36.727.226.597%*–
Carrera S PDK Cabriolet–26.4–––
Carrera T29.7––––
Carrera T PDK33.2––––
GT2 RS23.9––––
GT322.2––––
GT3 R21.2––––
GT3 RS22.1–22.1100%–
Speedster–20.6–––
Targa 431.7––––
Targa 4 GTS29.1––––
Targa 4 GTS PDK31.0––––
Targa 4 PDK35.8––––
Targa 4S31.4––––
Targa 4S PDK35.3––––
Turbo Cabriolet PDK28.5––––
Turbo PDK29.1––––
Turbo S Cabriolet PDK28.5––––
Turbo S PDK29.1–31.0–32.1107%–

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?

The site 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 dataset, with the official figures kept alongside, and reopened for new submissions.

Looking at a Porsche 911 (991/2) right now? Check the advert before you go and see it.

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 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.

Other Porsche models

Before you go and see it

Fuel economy is one line on the Porsche 911 (991/2) running-cost sheet. These guides cover the checks that stop you buying the wrong one.

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