Autoblog and Yahoo may earn commission from links in this article.Buying a used luxury SUV is where reliability separates the winners from the money pits, because German engineering that felt cutting-edge when new can become costly once the warranty expires. The Lexus NX built its reputation on the opposite approach, using a proven turbocharged four-cylinder and conservative electronics that rarely fail. Weighing the ownership records, repair costs, resale, and the typical problems of each, the NX is the clear pick, with the Q5 and X3 trailing on dependability even as they offer more power and polish.Lexus makes small changes to the 2021 NX lineup.LexusBrand track recordOn demonstrated dependability, the NX sits at the front. Lexus consistently ranks at or near the top for long-term reliability, and the 2021 NX benefits from a mature design with few surprises, since it was near the end of a well-sorted generation rather than an early-production model. Owners report a trouble-free ownership experience broken only by minor complaints, and it is common to see these SUVs cross 150,000 miles on original major components with nothing more than fluids, brakes, and tires.2021 Audi Q5 Sportback 45 TFSI QuattroJohn Beltz SnyderThe Q5 and X3 come from brands that build excellent vehicles but carry a reputation for more frequent and more expensive repairs as the miles pile up. Their turbocharged engines, adaptive suspensions, and dense electronics deliver a more engaging drive, but each added system is another thing that can eventually fail. That complexity is the core reason both land behind the Lexus on any long-term reliability measure.2021 BMW X3 xDrive 30e BMWRepair costs and resaleRunning costs follow the same pattern. The NX is inexpensive to maintain by luxury standards, with widely available parts and infrequent shop visits, while the Q5 and X3 tend to cost more per repair and visit the shop more often once out of warranty. For a used buyer, that gap compounds every year of ownership.2021 Lexus NX 300LexusAdvertisementAdvertisementResale tells the story just as clearly. A 2021 NX loses only about 39% of its value over five years, while the Q5 sheds roughly 58%, a massive difference that reflects how the market rates each one's durability. In used-market terms, a 2021 NX runs from about $25,779 to $35,999, while a Q5 spans roughly $21,041 to $33,496, and the X3 sits in a similar band to the Audi. The German pair are cheaper to buy used, but the Lexus gives far more of that money back at resale, often making it the lower-cost SUV to own despite the higher entry price.2021 Audi Q5 Sportback 45 TFSI QuattroJohn Beltz SnyderWhat goes wrong with eachThe specific trouble spots make the ranking concrete. The NX has the shortest list by far, with its most common complaints centering on the infotainment system and the awkward voice controls rather than anything mechanical. Its 2.0-liter turbocharged engine and conventional automatic are robust, and major drivetrain or engine failures are rare, which is the foundation of its reliability case.2021 BMW X3 xDrive 30eBMWThe Q5's issues cluster around its powertrain and electronics. Owners of the 2.0-liter turbo report carbon buildup and some oil consumption over time, along with MMI infotainment glitches and the higher maintenance bills that come with German mechanical complexity. Timing components, the water pump, and various electronic modules are among the parts owners should budget to service as the SUV ages, and the cost of that work at a specialist is a large part of why the Q5 sheds value so quickly. None of it makes the Q5 a bad SUV, but it demands more attention and money to keep right.The X3 carries a similar profile. Its most frequent complaints involve the iDrive system and smartphone connectivity, and owners report oil leaks and consumption on the turbocharged engines, along with cooling-system components like the water pump and thermostat that can fail as the miles climb. These are known BMW ownership items rather than freak occurrences, and budgeting for them is part of X3 life.So which one is the most reliable?The 2021 Lexus NX is the most reliable of the three, and it is not particularly close. It pairs the shortest problem list with the lowest running costs and the strongest resale, making it the obvious choice for a buyer who wants a used luxury SUV that will not become a financial burden. The Audi Q5 is the better pick for a buyer who prioritizes a more refined, powerful drive and a plusher cabin and is prepared for higher upkeep, and the BMW X3 rewards a driver who wants the sportiest handling of the group and accepts the same maintenance trade-off. Both are excellent vehicles to drive, but for pure dependability and low ownership costs, the NX wins clearly.AdvertisementAdvertisementThis story was originally published by Autoblog on Jul 7, 2026, where it first appeared in the Car Buying section. Add Autoblog as a Preferred Source by clicking here.