Can You Go Swimming With Toenail Fungus?

Swimming with toenail fungus is not medically prohibited, and no major health authority bans people with onychomycosis from entering a pool. That said, there are real considerations on both sides: the warm, wet environment can worsen your infection, and the fungi responsible for your nail problem can survive on pool decks and surrounding surfaces, creating a transmission pathway to other swimmers. The practical question is less “can you” and more “should you, and if so, how do you minimize harm to yourself and everyone else?”

The Real Risk Is Not the Water

When people picture spreading toenail fungus at a pool, they tend to imagine fungi floating through the chlorinated water from one swimmer’s foot to another. That is not how it typically works. Chlorine at properly maintained levels does reduce fungal loads in pool water. One study of indoor public pools found that pools with higher residual chlorine concentrations had less fungal contamination in the water, though fungi were still detected. The most common organisms recovered from pool water in that study were Aspergillus species, while only a single case of Trichophyton, the genus most responsible for toenail fungus, was found in the water itself.¹

The surfaces around the pool are a different story. Research on swimming pool environments consistently finds that floors, walkways, changing rooms, and the pool deck itself harbor far higher concentrations of clinically relevant fungi than the water does. A detailed investigation of an indoor pool facility found that the highest fungal concentrations appeared on floors at bottleneck points where swimmers converge while moving barefoot between rooms, like the transition from a changing room to a shower or from a shower to the pool deck.² That study recovered over 450 fungal isolates from surfaces, water, and air across the facility, with about half of the 111 species identified being clinically relevant. The dermatophytes most associated with toenail infections, Trichophyton interdigitale and Trichophyton rubrum, were found almost exclusively on floors rather than in the pool water.

A separate investigation examined the deck around a hospital physical therapy pool and found Fusarium, a mold increasingly implicated in nail infections, on nearly every surface sample collected over the course of a year. Two patients using that pool developed onychomycosis involving Fusarium within three months, raising the possibility that they picked it up from the pool surroundings.³

Can You Spread It to Other Swimmers?

The short answer is yes, though not in the dramatic way you might fear. Toenail fungus sheds fungal material primarily through tiny fragments of nail and skin that flake off as you walk. These fragments settle on warm, damp surfaces where the next barefoot person can pick them up. Multiple species responsible for nail infections, including T. rubrum and T. mentagrophytes, have been isolated from pool walkways, changing rooms, and foot-washing stations even at facilities that regularly disinfect with chlorine.⁴ Regular cleaning helps but does not eliminate the risk entirely, because fungal spores are remarkably persistent on porous surfaces like tile grout and textured anti-slip flooring.

You are unlikely to transmit your fungus to someone in the middle of the pool through the water column. The transmission scenario is more mundane: you walk from the locker room to the pool and back, leaving behind microscopic debris on every surface your feet touch. Another person walks the same path barefoot, and if their skin has small cracks or their immune system doesn’t fight off the spores quickly enough, a new infection begins. The risk you pose to others is highest in the areas where you walk, not where you swim.

Will Swimming Make Your Own Infection Worse?

Prolonged exposure to moisture softens nail tissue, and fungal organisms thrive in warm, humid conditions. If you swim regularly, your nails spend extended periods in exactly the kind of environment fungi prefer. The waterlogged nail plate becomes more permeable, which can let fungal organisms penetrate deeper. After you get out of the pool, the residual moisture trapped under and around the nail, especially if you put on closed-toe shoes right away, continues to create favorable conditions for fungal growth.

Chlorinated water is also mildly irritating to already-damaged nails. If your toenail fungus has caused cracking, lifting, or thickening of the nail, chlorine can dry out the surrounding skin and potentially widen small fissures that serve as entry points for secondary infections. None of this means one swim will drastically change the course of your infection, but frequent swimming without proper drying habits can undermine treatment you may already be undergoing.

If you are actively taking oral or topical antifungal medication, be aware that water exposure can wash away topical products applied to the nail. Applying a topical treatment right before a swim is essentially wasting it. Most dermatologists recommend applying topical antifungals after swimming and thoroughly drying your feet, rather than before.

Practical Steps If You Choose to Swim

There is no reason to give up swimming entirely because of toenail fungus, but a few habits make a meaningful difference for both your own recovery and the people around you.

• Wear pool shoes everywhere except in the water. Flip-flops or waterproof sandals on the pool deck, in the changing room, and in the shower dramatically reduce how much fungal material you deposit on shared surfaces and how much you pick up from others. Research on dermatophyte adhesion found that wearing socks or similarly woven foot coverings effectively blocked fungal passage through the material, while very thin barriers like stockings were not enough.⁵ For the pool setting, a rubber-soled sandal does the job.
• Dry thoroughly afterward. Pay special attention to the spaces between toes and around affected nails. A separate towel for your feet keeps you from transferring fungal spores to the rest of your body.
• Change out of wet footwear quickly. Sitting in damp socks or shoes after a pool visit extends the moist environment fungi need. Let your feet air-dry or use breathable shoes.
• Trim nails short and file down thickened areas. Less nail surface means less fungal material to shed, and shorter nails dry faster. Use your own nail tools and do not share them.
• Apply topical treatment after, not before. If your doctor has prescribed a topical antifungal lacquer or cream, the best time to use it is after your swim and after your nails are completely dry.

Who Faces Higher Risk at the Pool

Not everyone who walks barefoot across a contaminated pool deck will develop a nail infection. The fungi responsible for onychomycosis are everywhere, but they need the right conditions to establish themselves. Certain people are substantially more vulnerable.

Age is one of the strongest factors. Older adults have slower nail growth, reduced blood circulation to the feet, and more years of cumulative minor nail trauma, all of which make it easier for fungi to take hold. People with diabetes or compromised immune systems face a higher risk of both contracting and struggling to clear a fungal nail infection. Athletes and people who exercise regularly are another high-risk group. A large survey of people visiting general practitioners found that more than half had clinical signs of foot disease, and roughly two-thirds of those showed evidence of a superficial fungal infection, with a significant association between sporting activities and foot disease prevalence that was particularly strong in children.⁶

If you already have athlete’s foot, the risk of developing toenail fungus goes up considerably. The same dermatophytes cause both conditions, and an untreated skin infection on your foot provides a ready supply of organisms that can migrate into the nail. Swimming in public pools when you have active athlete’s foot is riskier for you and for the surfaces you touch than swimming with a contained toenail infection alone.

What Lives on Pool Surfaces Besides Dermatophytes

The conversation around swimming pools and fungi tends to focus on dermatophytes, the group of fungi most commonly responsible for athlete’s foot and toenail infections. But pool environments harbor a much broader range of fungi. Research on aquatic habitats, including swimming pools, has identified dozens of keratinophilic fungal species, organisms that feed on keratin, the protein that makes up nails, hair, and the outer layer of skin. One study recovered 22 keratinophilic species from swimming pools alone, including both known dermatophytes and related species with pathogenic potential.⁷

Aspergillus species are among the most commonly detected fungi in pool water. While Aspergillus is best known as a respiratory concern, some species can cause nail infections, particularly in people with weakened immune systems. The pool deck study that found Fusarium everywhere is another reminder that the fungal ecology around swimming pools extends well beyond the usual suspects.³ Fusarium nail infections are harder to treat than typical dermatophyte infections because Fusarium is naturally resistant to several standard antifungal drugs. For someone already dealing with toenail fungus, picking up a secondary mold infection from a pool environment could complicate treatment.

The Embarrassment Factor

For many people, the question of swimming with toenail fungus is not really a medical one. It is about how they feel being seen. Discolored, thickened, or crumbling toenails are hard to hide in sandals or at a pool, and the social discomfort this causes is well documented. A controlled study comparing over a thousand adults with and without onychomycosis found that those who had the infection reported feeling socially excluded, upset, and embarrassed by their condition.⁸ A review of the psychosocial literature on nail fungus found that embarrassment, low self-esteem, and social withdrawal were commonly reported consequences, and that the infection disrupted daily activities beyond what the physical symptoms alone would suggest.⁹

This matters because avoidance of swimming and other physical activities due to embarrassment creates a feedback loop. Exercise is beneficial for circulation, immune function, and overall health, all of which help your body fight fungal infections. Withdrawing from activities you enjoy because of how your nails look can worsen both your mental health and, indirectly, your physical ability to recover. If embarrassment is the main reason you are avoiding the pool, know that toenail fungus is extremely common and that other swimmers are far less likely to notice or care than you think.

Sharing Nail Tools and Other Overlooked Habits

Pool-related hygiene gets a lot of attention, but some of the riskiest behaviors happen at home or in the locker room before or after a swim. A large survey of municipal pool users found that while most reported changing towels after each pool visit, over 40% acknowledged sharing nail tools with others.¹⁰ Nail clippers, files, and cuticle tools that contact an infected nail carry viable fungal material and can transmit infections to other nails on your own feet, to your fingernails, or to another person who borrows them.

Shared towels are another vector, particularly if you dry your infected feet and then use the same towel on other body parts. The same goes for communal yoga mats, gym equipment foot pads, and shared shower shoes, though the last one is thankfully rare. If you use a gym or pool facility, treating your nail-care tools and towels as strictly personal is one of the most effective things you can do to avoid spreading your infection or picking up a new one.

Open Water, Hot Tubs, and Other Aquatic Settings

Most of the research on fungal contamination focuses on indoor public swimming pools, where warm water, enclosed spaces, and heavy foot traffic create ideal conditions. But people also swim in lakes, oceans, and hot tubs, and the risks differ.

Open freshwater bodies can harbor keratinophilic fungi. The same study that surveyed swimming pools for fungal ecology also sampled streams and found an even greater diversity of keratinophilic species in natural waterways, with 42 species recovered from stream sites compared to 22 from pools.⁷ That does not necessarily mean open water is riskier for your toenails; the absence of a shared deck and changing room removes the most important transmission surface. Saltwater may actually be mildly inhospitable to dermatophytes, though it is not a treatment. Hot tubs present their own concern: the higher temperature promotes fungal growth, and the smaller volume of water means disinfectant breaks down faster. If the hot tub is not meticulously maintained, the warm, turbulent water can be a more favorable environment for fungi than a standard pool.

Regardless of where you swim, the same principles apply: the water itself is usually less of a concern than the surfaces your bare feet contact getting into and out of it. Wear protective footwear wherever you walk, dry your feet thoroughly when you’re done, and keep your nails trimmed and treated. Swimming with toenail fungus is a manageable situation, not a reason to stay on land.