Things you should never put in the dishwasher

Dishwashers can run into serious problems if you put the wrong items in them. Here are some things you should never put in your dishwasher .

Dishwashers can do wonders in the kitchen and save you a lot of time. They are a magical machine that can replace a pile of dirty dishes with sparkling clean ones without you having to lift a finger. You love the ease and convenience of using a dishwasher until you find your favorite coffee mug or souvenir plate breaking?

This is a terrible mistake, but it happens to everyone who uses a dishwasher. There are ways to avoid these problems, but they can require a little effort and a return to hand-washing certain items. Here is a list of things you should never put in the dishwasher.

Avoid blunting the device

Knife 

A sharp knife is something everyone wants, and putting it in the dishwasher will dull the blade over time. So, hand wash your knives to keep them in tip-top condition.

Food planer

Like knives, you don't want the dishwasher to dull the blades in your food processor. This kitchen tool is best cleaned by hand.

Avoid fading

Copper cups and cookware

Copper is a classic yet trendy choice for cookware, and copper mugs are perfect for serving Moscow mules year-round. It's convenient to throw a copper mug in the dishwasher after a big holiday feast, but the drinkware won't survive multiple cycles in the dishwasher. Be sure to hand wash any copper or other precious metals to maintain their shine and avoid discoloration or tarnish.

Glass milk cup

Whether you're collecting vintage glass milk bowls from your aunt or vintage-inspired glassware from Anthropologie, make sure to hand wash them unless you're willing to risk discoloration.

Drinks, measuring cups or plates with letters

Over time, items with letters may fade after many cycles in the dishwasher. Measuring cups are useless once the letters are gone.

Classic Melamine Plate

Melamine plates and serving utensils have stood the test of time and have proven popular even as new materials have been invented. Classic Melamine products often feature patterns or designs that can tarnish in the dishwasher.

Gold Silverware

Unlike silverware, the shine on goldware will fade over time if washed in the dishwasher. This fading also happens to dishes with gold-colored metal designs, so to be safe, always wash them by hand.

Hand drawn

Your favorite hand-painted piece will never be the same once it starts to fade. To protect your plate, decorative mug, or any other painted item, wash your hands and scrub gently with a soft sponge so you don't rub off the paint.

Paper decal

If the mug has any decorative paper elements, they will likely fade in the dishwasher. Like text and other decorations, paper is too delicate to withstand the heat and hot air in a dishwasher.

Avoid structural failure

Insulated Cups & Mugs

Your favorite, trusty travel mug may not be airtight after a few washes. The same goes for insulated plastic or metal mugs. The insulation that holds the temperature of hot or cold liquids is compromised and loses its effectiveness. If you're going to put it in the dishwasher, choose the top rack and skip the high heat of the drying cycle.

Wooden Utensils & Cutting Boards

Hot water and the dry heat of a dishwasher can warp or crack wooden kitchenware and cutting boards, making them less useful. Heat dries out natural wood cutting boards, leaving them looking dull and discolored.

Pressure cooker lid

This is a big no-no. While your pressure cooker may be fine, the lid poses a safety issue. Dishwashers can warp or damage the rubber gasket on the lid, as well as damage the valve and vent that the lid uses when cooking. This can lead to a variety of problems, including an explosion of the pressure cooker.

Non-stick Pans & Grill Pans

Some nonstick cookware is labeled 'dishwasher safe,' but be aware that dishwashers can degrade the nonstick coating on pans, making them less effective. Read the label and proceed with caution.

Material protection

Aluminum cookware

Boiling dish soap can stain or tarnish aluminum cookware. Stainless steel is more likely to rust in the dishwasher, but check the label.

Cast iron pan

Your cast iron skillet is such a game-changer for classic muffins and cornbread that it would be a shame to lose it. Seasoning on a cast iron skillet is what makes it unique, and the dishwasher can damage the coating and eventually lead to rust.

Kareem Winters

Update 26 May 2025