Can Hot Water Kill Fungi? | The Laundry Temperature

You probably know the frustration of athlete’s foot that keeps coming back. You treat your feet, you dry between your toes, and still the itching returns. The culprit might be hiding in your laundry basket.

This article explains when hot water actually works against fungus, how hot you need to go, and why you should set the washing machine dial — not your bathtub faucet — for the job.

Why Laundry Heat Works Against Fungus

Fungal spores are tougher than many bacteria. They can survive regular warm-water wash cycles and transfer back to your skin the next time you put on that pair of socks. That’s why standard washing often fails to break the reinfection cycle.

Heat denatures the proteins that make up fungal cells. Once the water temperature climbs high enough, those structural proteins unravel, and the spore can no longer survive. The key is reaching and maintaining that temperature for the full cycle.

Research suggests the threshold sits around 140°F (60°C). A review of hygiene practices notes that kills fungus on socks, though it cautions that such high heat can damage delicate fabrics over time.

Why People Confuse Laundry With Foot Soaks

It makes intuitive sense: if hot water kills fungus on fabric, it should also kill fungus on your feet. But here’s the thing — your skin is not a sock. Soaking feet in hot water is not recommended for treating athlete’s foot. WebMD advises soaking feet in cool water instead to relieve itching and irritation, as hot water can worsen inflammation and dry out skin.

• Hot water for laundry: At 140°F, a washing machine cycle can kill fungal spores in socks, towels, and bedding. Use detergent and, for extra measure, a laundry disinfectant.
• Boiling as an alternative: Some sources suggest boiling socks for 10 minutes at 55-60°C (131-140°F) to kill lurking fungus. This works, but it’s tough on fabrics and best for white cotton items.
• Cool water for feet: Foot soaks for symptom relief should use cool or lukewarm water. Adding apple cider vinegar or tea tree oil to warm water may offer additional support, but these are home remedies with limited evidence.
• Warm environments encourage growth: Keeping feet wet for long periods and spending time in warm, moist places increases the risk of athlete’s foot. Drying thoroughly between toes is just as important as the wash cycle.

So the short answer is yes for your laundry, but no for a foot soak. Targeting the fungus in your socks breaks the reinfection loop that topical treatments alone can’t always fix.

The 140°F Threshold and What That Means for Your Wash

Most household washing machines have a “hot” setting, but not all hot water is created equal. Standard warm cycles usually hover around 90°F to 104°F, well below the 140°F mark needed to reliably kill fungal spores.

Some sources indicate that when socks worn by athlete’s foot patients were washed at 140°F, only about 6% tested positive for fungus afterward. That’s a dramatic reduction compared to warm-water washes, where researchers found much higher survival rates. For reference, WebMD recommends you wash socks in hottest water to help control the infection.

One important caveat: check your laundry labels. Delicate fabrics like wool, silk, and some synthetics can’t handle 140°F washes. For those items, consider using a laundry disinfectant additive approved for lower temperatures, or simply replace heavily infected items.

Practical Steps to Prevent Reinfection

A single hot-water wash won’t solve the problem if your bathroom floor, towels, and shoes still harbor spores. You need a coordinated approach for several weeks to break the cycle completely.

1. Wash all potentially infected items weekly. This includes socks, towels, bath mats, and gym clothes. Use the hottest water the fabric allows plus detergent and a laundry sanitizer.
2. Let shoes air out between wears. Fungus thrives in warm, dark, damp shoes. Rotate pairs so each pair gets at least 24 hours to dry completely. You can also use antifungal shoe sprays or powders.
3. Dry your feet thoroughly after every wash. Pay special attention between the toes. Use a clean towel each time, and don’t share towels with family members.
4. Apply topical antifungal creams or sprays as directed. Even after symptoms fade, many doctors recommend continuing treatment for one to two weeks to ensure the fungus is fully cleared.

Consistency matters more than any single step. The fungus is stubborn, but a few weeks of clean laundry and careful foot hygiene usually turns the tide.

What About Other Surfaces and Tools?

Hot water works for laundry, but what about your shower floor, nail clippers, or pedicure tools? For hard, non-porous surfaces, a solution of bleach and water (about 1 part bleach to 10 parts water) is typically effective. Let it sit for at least 10 minutes before rinsing.

For nail clippers and files, you can soak them in 70% isopropyl alcohol for 20 minutes or boil them for 10 minutes. Just remember to rinse and dry thoroughly afterward to prevent rust. Replace emery boards and pumice stones after treatment, as they can harbor spores in their porous surfaces.

Warm, moist environments increase risk for everyone, not just current sufferers. Keeping your bathroom well-ventilated, wiping down the shower after use, and wearing flip-flops in communal showers are smart prevention habits that cost almost nothing.

The Bottom Line

Hot water can kill fungi, but only when used correctly. The target is 140°F (60°C) on a washing machine cycle with detergent, applied to socks, towels, and bedding. Do not soak your feet in hot water for treatment — that can worsen irritation. Combine hot-water laundry with dry feet, clean shoes, and consistent antifungal treatment for the best results.

If your athlete’s foot persists after several weeks of these measures, or if you have diabetes or circulation issues, check with your primary care doctor or a podiatrist, who can prescribe stronger antifungal options and rule out other skin conditions that may mimic fungal infections.