Is an 18-Inch Dishwasher Right for You and Your Kitchen?

The good news about 18-inch dishwashers: They’ll save you half a foot of space compared with a 24-inch dishwasher, but they’re still quite flush with features. You’ll find similar options to larger machines in terms of hardware flexibility, like adjustable upper racks, tines that fold down, and removable silverware baskets. You can also find 18-inch dishwashers with stainless steel tubs, which resist stains better than plastic tubs do.

As with 24-inch dishwashers, 18-inch models come in a range of exterior styles. Some models have hidden controls and pocket handles, and some offer a choice of a stainless steel, black, or white finish.

In terms of technology, though, it’s hard to beat standard-sized models. Standard-sized models tend to have the bigger range of cycle options, as well as premium perks like targeted jets, interior lighting, a door that automatically opens at the end of a cycle, and WiFi connectivity. But 18-inch dishwashers still have plenty to offer. Some actually pack a good variety of cycle options into their slim build: quick wash, high-temperature wash, specific settings for china and crystal, and rinse-and-hold cycles. Many also have features like soil sensors and delayed start.

If you want a dishwasher in your kitchen fast, however, you might think twice about an 18-inch model. Each manufacturer might offer only a couple of versions, and they’re not always kept in stock. As a result, if you see one you like in a showroom, you may have to order it and wait for delivery, which can take about a week or more. In contrast, standard-sized machines, which are more in demand, tend to be readily available.

Despite their reduced capacity, the price of an 18-inch dishwasher is comparable to that of a standard-sized dishwasher. That’s because their features are similar. "You don’t buy an 18-inch dishwasher to save money or efficiency. You buy it to save space," says Dirk Sappok, director of category management at Miele. The 18-inch dishwashers in our ratings vary from around roughly $500 to just over $1,000; most of the standard-sized dishwashers cost around the same, though a few models land slightly below and considerably above that range.

You won’t necessarily save money on your water bill either. Larry Ciufo, CR’s senior test project leader for dishwashers, explains that water standards are based on how many place settings can fit into the dishwasher as opposed to the dishwasher’s dimensions. If your 18-inch dishwasher can fit eight or more place settings (the majority, in fact, can, says Nish Suvarnakar, CR’s senior market analyst for dishwashers), then it uses the same energy standard as a 24-inch model. That’s 3.5 gallons of water per cycle, as opposed to the 3.10 gallons per cycle for those that hold less than eight flatware place settings.

We test 18-inch models the same way we test standard 24-inch dishwashers—just with fewer dishes. Our testers soil each dish with baked-on food and load them according to the manual’s recommendations. They then scan the washed items with a photo-imaging machine to determine how clean they are.

To gauge drying performance, we zero in on how dry plastic sippy cups turn out after a cycle, because plastic is the material that’s toughest to get fully dry.

Our testers also sit through the entire dishwashing cycle to evaluate noise levels.

In terms of performance, the 18-inch dishwashers we evaluated weren’t all that bad—much to the surprise of our testers.

• Energy efficiency: Like the 24-inch dishwashers we’ve tested, the 18-inch models performed pretty well in this area, generally speaking.
• Noise: Also like their larger counterparts, the 18-inch dishwashers were mediocre when it came to keeping quiet. Ultra-quiet dishwashers of any size are, in fact, few and far between.
• Washing: When the dishwashers were loaded to the exact manual specifications, they all cleaned well. Proper positioning is especially important with 18-inch dishwashers, because every inch counts, says Ciufo. (In fact, the rack tines and cutlery trays in these machines are configured to discourage you from placing large dishes in the front and back—doing so can can block the detergent dispenser on the door or any special wash sections in the back.)
• Drying: A considerably larger proportion of 18-inch dishwashers we tested landed subpar scores in our drying test. That said, there were also a couple of standouts that earned above-average scores. "Drying depends on the type of drying system the model uses," says Ciufo, and not just on the dishwasher’s size.

The models below are the top-performing 18-inch choices in our tests. For more options in both small and standard sizes, explore our full dishwasher ratings. To learn more about dishwasher features and what might work best for you, see our comprehensive dishwasher buying guide.