Asking a question without stating your state, country isn't helpful. Go back in your user cp and input that.
It's very cold where i live and don't expect any good mileage. I know this was posted back in April which was just after March which is not a warm month!
Mileage is posted with optimal conditions like 70 degrees continously.

 

'14 CX-5 Grand Touring 2WD pushing 22k miles.
I have used the app for phone & computer called "FUELLY" from the car driving off the lot. Records fuel, cost, MPG, and many variables.
My average fuel over these 2 years is above 29 mpg.
My average the last 10 full-ups (all winter fuel (Calif. blends with Ethenol) and cold start short in-town trips) is 27.3 mpg.
My best tank took me 503.4 miles using 14.5 gallons. It was at altitude on the east slopes of the Sierra Nevada Mountain Range where we drove up every road (and dirt roads) as high as we could then back down. Fun vacation on US Hwy 395.
I like to refuel 20-40 miles after the miles remaining reads ZERO and have never run out of gas. Once I drove 440.3 miles and refilled 15.3 gallons (the tank capacity is listed as 14.8 gallons.)
All on 87 octane gasoline. Mobil 1 full synthetic 0W-20 oil every 6 months.
Tom in Brentwood, CA

 

It seems the Skyactive engines take a jump up in fuel economy somewhere between 3500 and 5000 miles. Do the Japanese have little gremlins in the PCM that limit you for break in? Who knows. I've just heard that more than once.

The MPG dash reading, just like ALL makes, is a convenience feature, not an exact science. You have to get old school, brush up on your math and calculate miles driven/gallons pumped=mpg.

 

For me, the dash numbers have been extremely accurate +/- 0.5mpg and yes the numbers have steadily risen after 3000 miles. Current mixed driving avg. stands at about 29.3mpg (GT-AWD) One of the most fuel efficient gasoline cars I've ever owned. I hope to see the avg. rise above 30 as the outside temps get higher.

 

Huh, and yet another testimony for the gremlins.

Nice to hear your dash is that accurate. Usually I hear up to a 3 +/- in dash readings. My Mazda is older and doesn't have that feature and my truck is a damn liar so I have to resort to old school.

 

I wish my 2015 touring at sea level in FL would pick it up... I'm averaging at best 21 MPG with 12k miles on it... been back to the dealer twice for it... never getting more than 300 miles on a tankfull

 

Hmmm, 300 miles on a full tank on the highway? That sounds pretty low.

A few questions:

• How much gas do you usually put in the tank when you fill from empty?
• How fast do you drive on the highway?
• On long trips, is said trip all highway or is it more of a mixture of highway and local or even all highway but with lots of traffic?

 

I said average, not highway... that said usually put 14+ gallons in the tank.
My 2007 Mazda6 got better gas mileage 25 - 27 around town, 32-34 highway... I drive the CX easier than I ever drove the 6.