How To Clean LEGO Pieces: A Complete Guide (2026 Update)

Category: Guides

By BrickBucks Team

From a dusty childhood collection to a garage-sale haul, here is the safe, step-by-step way to clean LEGO bricks without warping or fading them.

The Safe Way To Wash LEGO Parts

The LEGO Group's own guidance is clear: hand wash with lukewarm water and mild detergent. The maximum safe water temperature is 104°F (40°C). Anything hotter can deform ABS plastic, weaken the precision-molded studs, and ruin a brick's ability to clutch.

Start by sorting bricks into batches. Pull aside any pieces with stickers, any electrical parts (Power Functions motors, light bricks, battery boxes), and any minifigures with printed elements. These three groups need different treatment than standard bricks.

For the standard bricks, fill a plastic basin or bowl with lukewarm water and add a small squirt of mild dish soap — the kind you would use on dishes by hand, not anything labeled antibacterial or heavy duty. Add the bricks, swirl gently with your hand, and let exceptionally dirty pieces soak for 10 to 20 minutes. Rinse thoroughly under clean running water, ideally through a colander so no small pieces escape.

How To Dry LEGO Bricks Safely

Drying is where most cleaning attempts go wrong. The LEGO Group specifically warns against using hair dryers, microwaves, ovens, or direct sunlight. Heat warps the plastic and direct sunlight fades the colors — sometimes dramatically.

The right approach is straightforward: spread an absorbent towel on a flat surface and lay the bricks out in a single layer with as much space between pieces as possible. If you have an oscillating fan, set it to a cool setting and aim it across the towel — this reduces drying time from a couple of days to a few hours. Flip the pieces over once or twice during drying so water does not pool inside the hollow undersides of bricks.

Patience matters here. ABS bricks have nooks, undersides, and small enclosed channels that hold water for surprisingly long. If you bag damp bricks for storage, you will find mildew when you open the bag a few weeks later. Wait until every brick is completely dry to the touch — including the inside of any enclosed elements like windshields and panels.

The Tools That Make LEGO Cleaning Easier

You do not need a specialized kit, but a few inexpensive supplies dramatically speed up the process when you are cleaning a large quantity of pieces:

• A plastic basin or bin dedicated to LEGO cleaning. A salad spinner works surprisingly well as a final rinse and partial dry stage.
• A brick separator for prying apart pieces that have been clutched together for years. Cleaning two stuck-together bricks as a unit means the contact surfaces never actually get clean.
• Mild dish detergent. Avoid bleach, ammonia, and any abrasive cleaner. These can discolor bricks and dull their surfaces permanently.
• A soft-bristle toothbrush for working dirt out of textured pieces, minifigure faces, and small studs.
• Mesh laundry bags in assorted sizes, which let you wash bulk lots without losing small pieces down the drain.
• A colander or mesh strainer for rinsing.
• An absorbent towel and a small fan for the drying stage.

Can You Put LEGO in the Dishwasher or Washing Machine?

The official LEGO answer is no. Heated dry cycles in a dishwasher can exceed 150°F, which is well above the safe threshold and will visibly warp bricks over time. Washing machines combine heat with mechanical agitation that can crack thin pieces.

That said, plenty of resellers and collectors clean large lots in dishwashers with reasonable success. The recipe is the lowest temperature wash setting, no heated dry, and bricks placed inside zipped mesh bags so they cannot block the drain or rattle against the heating element. Use no detergent or only a small amount of plain dish soap — never use dishwasher detergent, which is too harsh.

Even with these precautions you are operating outside LEGO's recommendations. Any warping or color shift is irreversible. If you are processing a high-value lot — anything with rare or printed parts — stick with hand washing.

Sanitizing Used LEGO

If you have just bought a bulk lot at a yard sale, an estate sale, or on Facebook Marketplace, you do not know where those bricks have been. A standard hand wash kills most surface bacteria, but if you want a true sanitizing step, add about a tablespoon of plain white vinegar per gallon of soapy water. The acetic acid kills the bacteria the soap leaves behind without damaging ABS plastic.

Rinse extra thoroughly after a vinegar wash — residual vinegar is harmless but smells unpleasant for a few days if it dries onto the bricks. For minifigures and other parts you intend to resell, a sanitized batch is also a useful selling point in your listing photos and descriptions. We cover product photography and listing best practices in our guide to selling on BrickLink.

Removing Permanent Marker, Smoke, and Other Stains

For permanent marker on bricks, 99% isopropyl alcohol is the safe and effective solvent. Apply a small amount to a cotton swab or microfiber cloth and dab — do not flood the brick. Avoid nail polish remover, which has a lower alcohol percentage and additives that can dull the brick's surface.

For a smoke or musty smell, the baking soda and vinegar method is the most reliable. Make a paste of baking soda and water, coat the affected bricks, and let them sit for a few hours. Mist with a 50/50 vinegar-water solution; the resulting fizzing reaction lifts odors out of the plastic. Rinse thoroughly and air dry. For severely smoke-damaged collections you may need to repeat the process two or three times before the smell fully disappears.

For dull or yellowed clear pieces, a brief soak in a clear floor polish (the kind with acrylic in it) restores their gloss and hides micro-scratches. Submerge briefly, lift out, and let dry on a clean surface — do not touch the surfaces while wet. A well-cleaned, polished clear element looks essentially brand new and adds noticeable value when you part out a set, which we break down in our part-out strategy guide.