According to market tracker HybridCars.com, the two South Korean automakers sold 4,976 vehicles that make use of both an internal combustion engine and electric motor to get high fuel mileage.
The total represents a 9 percent increase from 4,566 units sold in the previous month and more than a twofold surge compared with the year before. In July 2016, Hyundai and Kia sold 2,069 hybrids in the key North American market.
|Kia Motors Niro hybrid crossover (Yonhap)|
Combined, the two carmakers made up 17.1 percent of the hybrid market, up a meaningful 1.9 percentage points from June.
The second-place spot marks the first time since April 2015 that Hyundai and Kia beat their US rival in the hybrid sector.
HybridCars.com attributed Ford's weak showing to the drop in demand for its Fusion hybrid model that sold 3,186 units last month. Ford's market share fell to 12.5 percent, with Toyota remaining at the top with a strong 61.3 percent hold in terms of sales.
Ford's numbers backtracked from 23.6 percent the month before, while Toyota's shot up from 53.2 percent.
The vehicle review site added that the relatively good performance by Hyundai and Kia was largely due to strong consumer demand for the Niro crossover-type hybrid that sold 2,763 vehicles last month, which also placed the Kia car third in terms of sales after Toyota's Prius and RAV4 hybrids.
Hyundai's Ioniq hatchback, which first hit show windows in March, sold 1,209 vehicles, placing it eighth, with sales of the Sonata and Optima midsize hybrid sedans reaching 739 and 265 units, respectively, in the cited month.
HybridCars.com said the growth in the US hybrid market is being fueled by the Kia Niro, Ford Fusion, Honda Accord, Toyota Highlander and Hyundai Ioniq models.
Besides conventional hybrid cars, Hyundai and Kia sold 200 Sonata and 130 Optima plug-in hybrid electric vehicles in the United States, with sales of the Kia Soul pure electric vehicles hitting 145, up 45 percent from the month before, with the Ioniq EV reaching 43. (Yonhap)