The mid-size sedan was once the default for a majority of U.S. car buyers.
While the segment's position has been eroded by the rise of crossover utility vehicles of many sizes, these sedans still remain quite popular.
Given the number of options available among hybrid mid-size sedans, that should remain the case among buyers who want passenger vehicles with high fuel-economy ratings.
Many of the top-selling mid-size sedans offer a hybrid option, with the segment average hovering in the 40-mpg range.
We've listed all of the 2017-model-year hybrid mid-size sedans here, in order of EPA combined fuel economy.
We've also added in the upcoming 2018 Toyota Camry Hybrid, the only updated mid-size sedan hybrid expected for 2018, and one that is gunning for "best-in-class" fuel economy.
2017 Honda Accord Hybrid
2017 Honda Accord HybridEnlarge Photo
2017 Honda Accord Hybrid (48 mpg)
The Accord Hybrid is the most fuel-efficient mid-size sedan, although the redesigned 2018 Toyota Camry Hybrid may surpass it.
Honda's hybrid mid-size sedan returned for the 2017 model year after skipping 2016.
It uses an updated version of the two-motor powertrain fitted to the 2014 and 2015 Accord Hybrid.
ALSO SEE: 2017 Honda Accord Hybrid first drive (Jul 2016)
The hybrid system is paired with a 2.0-liter 4-cylinder engine that uses the lean Atkinson Cycle combustion sequence for the highest output on the least fuel.
The gasoline acts primarily as a generator, only powering the wheels directly in limited circumstances.
Besides the powertrain, the Accord Hybrid is largely similar to other versions of the Accord sedan, which remains fairly popular among consumers.
2017 Chevrolet Malibu
2017 Chevrolet MalibuEnlarge Photo
2017 Chevrolet Malibu Hybrid (46 mpg)
The current-generation Chevy Malibu Hybrid was launched as a 2016 model, and remains largely unchanged for 2017.
Its powertrain borrows heavily from the Chevy Volt plug-in hybrid, helping the Malibu achieve relatively high fuel economy while giving General Motors economies of scale.
CHECK OUT: 2016 Chevrolet Malibu Hybrid: First Drive Of Sedan Using Volt Hybrid System (Jan 2016)
The Malibu's electric-drive system is a modified version of the Voltec system, and the sedan shares a blended brake-regeneration system with the Volt as well.
However, the Malibu uses its own 1.8-liter 4-cylinder gasoline engine and a much smaller battery pack—1.5 kilowatt-hours, compared to the Volt's 18.4 kwh.
2017 Ford Fusion Hybrid
2017 Ford Fusion HybridEnlarge Photo
2017 Ford Fusion Hybrid (42 mpg)
The Fusion Hybrid received some notable updates for 2017, resulting in a slight increase in fuel efficiency.
Combined fuel economy is up 1 mpg, despite changes to EPA testing standards for the 2017 model year that have caused ratings for many cars to fall slightly.
READ MORE: 2017 Ford Fusion Hybrid and Energi: how engineers increased fuel efficiency (Sep 2016)
The powertrain—encompassing a 2.0-liter Atkinson-cycle 4-cylinder engine and electric motor—remains unchanged.
But Ford engineers tweaked the software, and squeezed efficiency gains from other areas, such as aerodynamics and even a new, low-drag brake-caliper design.
As before, the Fusion Hybrid is paired with a Fusion Energi plug-in hybrid model, with an EPA-rated 22 miles of electric-driving range.