With the dominance of SUVs in the U.S. car market, it would be easy to assume that they're a safe bet for better sales every month and year. Reality isn't so kind, though, as Honda is seeing this January. In a rather big surprise, all of its SUV models saw worse sales this January than last, with two exceptions. Not only that, but Acura's SUVs had a similarly rough month.Honda Honda's Biggest Performed Best What's also surprising about Honda's SUV sales performance this month is that its bestseller is one of this month's underachievers. Yes, the CR-V was down for January, but at least it was just barely down. Its decline was just 1% from 27,280 to 27,019, and it retained the top sales of any model.Honda The HR-V did quite a bit worse, dropping by 19.7% from 11,817 last January to 9,488 for this January. The biggest loser for the month, though, was the Prologue electric SUV. It was down a whopping 82.9% over last January, going from 3,744 sales to just 664.Nicole Wakelin/CarBuzz/Valnet The sole bright spots came from Honda's biggest SUVs, the Passport and Pilot. The Passport actually had an amazing January, going from 2,643 units last January to 4,320, an increase of 63.5%. The Pilot had a more modest improvement of 8.6%, climbing from 8,849 sales to 9,607. The gains from these two SUVs wasn't enough to offset the losses, though, with Honda's SUVs dropping from 54,333 to 51,098 between Januarys. It's A Similar Story At Acura Acura's SUV line wasn't in great shape, either, but the reasons are a little different. Half of the brand's SUVs were down significantly, but both of those models either have been or are being discontinued. The end for the electric ZDX was announced last fall, and the 15 units that were sold this January (compared to 1,384 last January) reflects that. The CR-V-sized RDX sales reduction wasn't as bad, dropping 26.7% to 1,901, but that wasn't enough to save it. Its demise was announced in the same month.Acura The long-running MDX was effectively level, selling just 20 more units this January for a total of 2,986. The ADX, based on the Honda HR-V, sold 2,387 units, all of which were pure increase since the model wasn't on sale last January. The other good news for Acura is that the ADX's sales more than make up for the losses from RDX and ZDX, bringing the total SUV sales to 7,289 versus 6,944 last January. Honda's Other Utility Vehicles Honda has two other models that fall into the brand's "truck" category with its SUVs. We've already talked about one of them, the Odyssey minivan, and how it had a solid January, with sales that grew by 5.7%. The other is an actual truck, the Ridgeline. It had a sales improvement of 26.5%, making it the third most-improved by percentage behind the Accord and the Passport. Its total sales came to 3,625. Both the Odyssey's and Ridgeline's improvements weren't quite enough to offset the losses from other models, so the overall Honda truck line was still down 3.5% over last January.