“Are my figures quite unusual or is it normal? Why am I not getting advertised mpg?” Normal. Mileage depends greatly on driving conditions. You will get worse mileage if all you drive is short trips. Driving over 63 MPH/100 KPH will reduce your mileage. Using E10 gas instead of pure gasoline will reduce your mileage. Putting a big car top carrier on a Prius DRASTICALLY reduces mileage because the ICE runs nearly 100% of the time at highway speeds. (We have a Sears Ex-Cargo on Thule roof rails. It costs 10 MPG to drive with it on. It's still cheaper to use than a minivan or an SUV.) My wife and I own four Priuses. Our twins drive two of them. My old 2009 Touring Edition (with wide high performance tires) got 42 MPG new, and gets 42 MPG now, after 187,000 miles. My wife’s old 2009 got 46 MPG at 49,000 miles when we bought it used, and gets 46 MPG now, at 167,000 miles. My 2010 Prius 4 got 43 MPG when I bought it used last year with 53,000 miles, and gets 43 MPG now. My sister-in-law has the exact same car I do, and gets about the same mileage. My wife’s 2015 Prius v wagon got 40 MPG when she bought is used at 48,000 miles, and gets 41 MPG now. “Does it mean I need to work more on how I drive? Or is this kind of variation between specific cars possible (+/- 5 mpg)? Will it improve on future fill ups?” You might be able to learn some pulse and glide techniques that would improve mileage slightly. We just drive, doing whatever the heck we always have. We get what we get, knowing that the ratings are based on conditions we do not encounter. We don’t worry about it. The MPG calculator in the Prius is optimistic… anywhere from 1.5 to 3.5 MPG. I always subtract 2 MPG if I want a reasonably honest figure. When I calculate mileage by hand, I average at least five tanks of gas together. That’s because it is very difficult to fill the tank to exactly the same level at every pump. TIRES can affect mileage 1-3 MPG, in my experience. I like Ecopia 422+ for mileage. I don’t like their handling. I like Michelins for handling, but their mileage is worse. Winter weather reduces mileage a lot, as does Summer driving. When you use HVAC, the car burns more gas to generate more power to run it. Here in the South, ridiculously high humidity forces us to run the AC all the time in Summer. Keeping your car in a garage will do wonders for its longevity and its mileage. It won’t have to warm up as much in Winter, and in shade, you won’t cook the battery as much in Summer. The worst thing for mileage, though, is NOT getting the car warmed up fully and driving a substantial portion of the time with that warm engine. It burns a lot of gas at startup, just to get the engine warm. I used to live in Charlotte, a VERY spread-out city with 750,000 people and a metro area of 2.5 million. I had at least a 30 minute commute to work, which was usually 45 minutes or more in the afternoon. I consistently got 42-44 MPG on that route in my 2009, over a four year period, even with 17 traffic lights. Here in High Point, a town of 115,000, almost everything is close to us. So most trips are less than 15 minutes (many are 10 minutes). Mileage falls off when I don’t do anything but drive around town (post office, gas station, grocery store, restaurants and shops). Where our Priuses really shine is on long road trips. We nearly always get a couple more MPG on the way to Florida from NC, partly because we take back roads for about 1/3 of the trip, where the speed limit is 55. Traffic jams on I-95 reduce speeds in SC to about 40 MPH on average, so that helps, too. I guess what I’m saying, really, is don’t sweat your mileage results too much. They’re really best for comparing car models you might purchase. As a guide to real-world performance, they’re not that accurate. The sticker on my 2009 Touring Edition 5 said 60MPG EPA Highway. In my dreams… Consumer Reports' real-world road test said 42. I got 42. I'm happy.