What Is Rinse Aid and Do You Really Need It? An Expert Explains All

While rinse aid might seem like a cleaning product upsell you can do without, many dishwashers are designed to work most effectively when you add this inexpensive liquid to your cleaning routine. But, is it entirely necessary to use? We spoke with an expert to explain what rinse aid is, how it works, and whether you really need to use it to achieve sparkling clean dishes every time you run your dishwasher.

What Is Rinse Aid?

Rinse aid is a drying agent designed to boost your dishwasher's rinse cycle, making the drying cycle more effective. It helps pull water off your glasses, dishes, and plates. Rinse aid removes evidence of water spots, mineral deposits, and hard water, leaving your dishes shinier and cleaner, and gives energy-efficient dishwashers the same power as heat-thirsty older versions.

"Rinse aid improves dishwasher performance by helping dishes dry faster and reducing water spots," says James Fleming, appliance expert with home care and maintenance service Frontdoor. "Rinse aid helps water run off dishes and the inside of the dishwasher during the final rinse cycle, leaving dishes drier and reducing streaks, chalky residue, and filming. It can also help eliminate odors by reducing moisture buildup in the wash bin."

How Rinse Aid Works

"Rinse aid works by lowering the surface tension of water, which causes it to sheet and slide off dishes instead of forming droplets that can leave water spots," Fleming says. "A common example of liquid detergent used in combination with a rinse aid are prepackaged dishwasher pods."

Rinse aid comes in multiple versions: some are made with phosphates and other synthetic chemicals, while others are gentler alternatives made with vinegar, citric acid, and other natural ingredients, says Fleming. These products can be used in combination with liquid or powder detergent.

Do You Have to Use Rinse Aid?

Energy-efficiency requirements for dishwashers have changed the way they dry, trading higher heat cycles for steam. Dishwasher manufacturers recommend using rinse aid to remove as much water as possible from the dishes before the dry cycle. "Rinse aid can help reduce streaks on dishes by promoting better water sheeting and drying, soften the water entering the dishwasher from the home, and can also help prevent mineral deposits from forming in your dishwasher," says Fleming. "Rinse aid can help with drying and prevent water spots, especially if you have hard water—it can also make your dishes shine."

While most dishwasher manufacturers expect owners to use rinse aid, it's not required: "You can skip it if your dishes are clean and dry without it," says Fleming. "From experience, dishes that go through dishwashers that operate at a higher water temperature in a stainless-steel dishwasher tub will dry better without using rinse aid than those washed in a plastic tub dishwasher. Plastics, in most cases, will not dry 100 percent in the dishwasher—even with a rinse aid."

How to Use Rinse Aid

Adding rinse aid into your dishwashing routine is simple and foolproof: Most dishwashers include a rinse aid compartment with a fill line that indicates how much you need. Check the compartment and refill as needed, or check your dishwasher for a "low rinse aid" indicator light. The rinse aid will be automatically dispensed during the cycle.

"In figuring out how much rinse aid to use, a best practice is to refer to your dishwasher’s owner’s manual, as the amount of rinse aid across assorted brands and models may vary," says Fleming.