Items You Should Never Put in the Dishwasher

A dishwasher is a time-saving and convenient kitchen appliance. But are you making the mistake of washing all kinds of utensils, dishes, and cups—no matter what they’re made of—in the dishwasher?

If your answer is yes, you may be damaging your kitchenware and even the dishwasher itself!

To protect both, here are the items you should never put in the dishwasher:

🪵 Wooden utensils, bowls & cutting boards

Dishwasher detergents strip away the natural oils that protect wood from drying out. Without these oils, wood cracks and warps.

✅ Wash by hand with mild soap and warm water. Avoid soaking, which causes swelling and distortion.

💡 For disinfecting, use a light solution of chlorine bleach (¼ cup) mixed with warm water (½ gallon).

🔪 Kitchen knives

Washing knives in the dishwasher dulls their blades, causes rust, and loosens or splits wooden handles.

✅ Hand-wash and dry immediately.

🥄 Graters, sieves & sharp tools

Dishwashers can cause rust, and food particles often get trapped in the mesh.

✅ Scrub by hand for best results.

🍳 Cast-iron cookware

Dishwasher detergent removes the protective oil seasoning, leaving the pan prone to rust and unusable.

✅ Wash by hand, dry thoroughly, and rub lightly with oil.

🥛 Milk glass (opaque glassware)

Heat and detergents can cause vintage milk glass to yellow over time.

✅ Hand-wash to preserve its beauty.

🥘 Aluminum pans & pots

Dishwashers make aluminum dull and spotted, even if labeled “dishwasher safe.”

✅ Wash by hand. For discoloration, rub with a paste of cream of tartar and warm water.

🥉 Copper pans & mugs

Dishwasher detergents damage copper’s polished finish.

✅ Hand-wash only.

🪨 Natural stone kitchen tools

Examples: pizza stones, granite cutting boards, mortar & pestle.

Dishwasher heat and detergents cause cracks and loss of shine.

✅ Clean with water and a brush, adding a little dish soap if needed.

🎀 Decorative kitchen items

Salt & pepper shakers, ceramic figurines, wooden décor, etc.

These are fragile and can easily chip or break in the dishwasher.

✅ Wash gently by hand.

☕ Heat-insulated mugs

Dishwasher heat and tight spaces can weaken their insulation.

✅ Wash by hand with a bottle brush.

🍲 Pressure cooker lids

While the pot may be safe, lids contain valves and seals that can trap food and break down from detergents.

✅ Wash lids by hand only.

🍳 Nonstick pans

Even if marked dishwasher-safe, detergents and high heat degrade nonstick coating. Damaged coatings can release harmful chemicals.

✅ Hand-wash carefully, replace if scratched or peeling.

🍶 Ceramic-coated cookware

These aren’t pure ceramic—they’re usually metal with a ceramic coating. Dishwasher detergents can strip or discolor the finish.

✅ Hand-wash with mild soap.

🍽️ Acrylic or melamine plates

Bright, lightweight, and shatterproof—but dishwashers cause fading, cracking, and warping.

✅ Hand-wash to maintain color and durability.

🖌️ Printed or hand-painted glassware

Dishwasher detergents and strong spray can strip designs in just a few washes.

✅ Wash gently by hand.

🥡 Thin plastic containers

Butter tubs and takeout containers may warp or melt in dishwasher heat.

✅ If washed, place on the top rack and avoid heated drying.

🏷️ Containers with paper labels

Paper and adhesive come off, clogging the dishwasher filter.

✅ Remove labels before washing jars.

✨ Gold-colored flatware

Detergents dull or remove the gold finish.