How to Clean a Retainer Properly (2026 Guide)

Key takeaways

• Clean your retainer every time you brush your teeth, using cool water and a soft brush.
• Never use hot water or toothpaste. Hot water can warp it and toothpaste scratches it.
• A smelly or cloudy retainer is a sign bacteria and plaque are building up.
• Ultrasonic cleaning reaches the tiny grooves a brush can't.

Your retainer sits against your teeth for hours a day, so it picks up the same plaque and bacteria as your teeth do. If you don't clean it properly, it can start to smell, turn cloudy and even put your teeth at risk. Here's how to clean a retainer the right way.

Step 1: Rinse it straight away

Every time you take your retainer out, rinse it under cool running water. This stops saliva and food drying onto it.

Step 2: Brush it gently

Use a soft toothbrush kept just for your retainer. NHS orthodontic teams at Queen Victoria Hospital recommend liquid soap rather than toothpaste, because toothpaste "will scratch them and make them cloudy". Those tiny scratches then trap even more bacteria.

Step 3: Keep it away from heat

Never use hot or boiling water. The Royal Berkshire NHS Trust warns that hot water can warp a retainer so it no longer fits properly. Keep it out of hot cars and away from radiators too.

Step 4: Give it a deep clean

Brushing cleans the surface, but plaque hides in the small grooves that hold your teeth in place. A 2022 systematic review of aligner cleaning in the journal Healthcare found the most effective approach combines a mechanical clean with a cleaning agent, rather than relying on one method.

That's where an ultrasonic cleaner helps. Ultrasound sends sound waves through water, creating millions of tiny bubbles that lift dirt from every crevice. In lab research carried out with Robert Gordon University, ultrasonic cleaning at 42 to 45kHz reduced viable bacteria on dental appliances by 88.6% after 5 minutes and 99.97% after 10 minutes. See the research

Step 5: Store it in its case

When it's not in your mouth, keep your retainer in its case. Wrapping it in a tissue is the most common way retainers get thrown away by mistake.

Why does my retainer smell?

A smelly retainer is usually caused by bacteria and plaque building up in the grooves. Brushing alone often can't reach them. Rinse after every wear, brush daily with liquid soap, and deep clean regularly. If the smell comes back quickly, your retainer may have scratches that trap bacteria, so ask your dentist.

Why is my retainer cloudy?

Cloudiness usually comes from a build-up of minerals from saliva (tartar), plaque, or tiny scratches from toothpaste. A regular deep clean helps stop the build-up. Scratches can't be undone, which is why it's worth avoiding toothpaste from day one.

Common questions

How often should I clean my retainer? Rinse it every time you take it out, brush it at least once a day, and deep clean it a few times a week.

Can I clean my retainer with toothpaste? It's best not to. Most toothpastes are mildly abrasive and can scratch the plastic.

Can I use boiling water? No. Heat can warp the retainer so it no longer fits.

Shop the clean: Sonic Spa Go is a cordless ultrasonic cleaner that cleans retainers, aligners and guards with just water, in a 3-minute cycle.