Swimming with Contact Lenses: Risks, Safety Rules & What to Do If You Already Have

A sunny day at the beach, a pool session, or a spontaneous dip: these are the moments when many contact lens wearers realise they forgot to take their lenses out before getting in the water. The guidance from UK eye care professionals is consistent: swimming with contact lenses carries real risks that are worth understanding. This guide explains why, how serious those risks are in different types of water, what to do if you have already been in with your lenses, and what actually works for active swimmers.

Quick Answer

Swimming with contact lenses is not recommended by UK eye care bodies including the BCLA and AOP. Pool water, sea water, rivers, lakes, and hot tubs all contain microorganisms that soft lenses absorb, significantly increasing infection risk. If you must swim, the BCLA advises using daily disposable lenses with watertight goggles and discarding the lenses immediately afterwards. Never reuse lenses that have been exposed to any water.

Why Swimming with Contact Lenses Is Risky

Soft contact lenses are porous by design. They must allow oxygen to pass through to the cornea, but this same porosity means they readily absorb whatever is in the water around them. In any natural or treated body of water, that includes chemicals, minerals, bacteria, viruses, and in some cases, dangerous microscopic organisms. The lens then holds these contaminants in close contact with the surface of the eye for as long as it remains in place.

Acanthamoeba Keratitis: The Most Serious Risk

Acanthamoeba is a microscopic organism found in tap water, swimming pools, rivers, lakes, and the sea. When it attaches to a contact lens and reaches the cornea, it can cause Acanthamoeba keratitis, a severe infection that is extremely painful, resistant to standard antibiotic treatment, and in advanced cases can lead to permanent vision loss. The British Contact Lens Association (BCLA) reports that 85% of Acanthamoeba keratitis cases in the UK occur in contact lens wearers.

A critical and widely misunderstood point is that the chlorine used to treat swimming pools does not reliably kill Acanthamoeba. The organism exists in two forms: an active trophozoite state and a dormant cyst state. The cysts are highly resistant to chemical disinfection, including chlorine at normal pool concentrations. This means a properly maintained pool is not a safe environment for contact lens wear, regardless of how clean the water looks or smells.

Chlorine, pH and Lens Behaviour

UK public swimming pools are maintained to Health and Safety Executive standards, with free chlorine levels of 1.0 to 3.0 mg/l and pH between 7.2 and 7.6. For most swimmers without contact lenses these levels cause little problem, but for lens wearers they create two specific issues. First, chlorine is absorbed by soft lens material and can later be released onto the eye surface, causing prolonged irritation after swimming. Second, fluctuations in water pH can cause soft lenses to swell, tighten against the cornea, and become difficult and painful to remove without risking corneal abrasion.

Lens Movement and Loss

Even without infection risk, water exposure creates practical problems. Jumping into water, opening eyes underwater, or being splashed can cause a lens to shift position, fold, or dislodge entirely from the eye. Rigid gas permeable lenses are particularly vulnerable to being washed away. Soft coloured lenses are more likely to stay in place, but their larger diameter makes dislodgement more disorienting when it does happen.

The Association of Optometrists (AOP) states that swimming-related eye infections are possible in anyone, but contact lens wearers face significantly greater risk than non-wearers. This applies to all types of water, including treated swimming pools.

Risk Level by Water Type

Not all water carries the same level of risk for contact lens wearers. The table below summarises the key differences between the most common situations, from the swimming pool to the shower.

Natural bodies of water such as lakes, rivers, and the open sea consistently carry the highest risk because they contain high concentrations of bacteria and Acanthamoeba without any chemical treatment to reduce them. Hot tubs are more dangerous than standard pools because the warmer temperature accelerates bacterial growth and reduces the effective concentration of chlorine. Even the shower, which many lens wearers overlook entirely, carries low but real risk from Acanthamoeba present in tap water.

If You Must Swim: The BCLA Protocol

There are situations where removing lenses before swimming is not possible, whether through oversight or necessity. In these cases, the British Contact Lens Association advises the following approach to reduce, though not eliminate, risk. For broader guidance on safe lens wear practices, see our overview of safe contact lens wear.

Use daily disposable lenses only. Monthly or bi-weekly lenses that have been exposed to water should always be discarded. Daily disposables are the least harmful option because they are used once and thrown away, eliminating any ongoing risk of contaminated lenses being reinserted. Never attempt to clean and reuse a lens that has been in contact with pool or sea water.

Wear watertight, well-fitted goggles throughout. The goggles must seal completely around the eye socket and remain in place during the entire time you are in the water. Loose-fitting goggles that allow water to seep in provide a false sense of security. If your goggles come off at any point, treat your lenses as contaminated.

Remove and discard lenses immediately after leaving the water. Do not wait until you get home. Carry a spare pair of glasses, a lens case, and fresh solution so you can remove your lenses poolside. If you are wearing daily disposables, discard them and insert a fresh pair only once your eyes have been rinsed with sterile saline.

These precautions reduce risk but do not eliminate it entirely. The safest approach remains removing contact lenses before any water activity without exception.

If you need daily lenses for an occasion involving water, Bella's Daily Collection provides soft coloured lenses designed for single-day use: Bella Daily Contact Lenses.

What to Do If You Have Already Swum with Lenses In

If you realise you have been in the water while wearing your contact lenses, acting quickly and following the right steps reduces the likelihood of developing complications. This is one of the most searched-for situations by lens wearers and one of the least well covered by existing UK guidance. For context on how different lens types respond to hygiene issues, see our beginner's guide to contact lenses.

Step 1: Remove the lenses immediately. As soon as you are out of the water, wash your hands thoroughly with soap and water, dry them with a lint-free cloth, and remove both lenses.

Step 2: Discard the lenses. Do not attempt to rinse them with solution and reinsert them, even if they feel comfortable and the water seemed clean. Contamination is not visible and not always felt immediately.

Step 3: Rinse your eyes. Use sterile saline solution or preservative-free rewetting drops to flush both eyes gently. Do not use tap water to rinse your eyes.

Step 4: Give your eyes a rest from lenses. Wear glasses for the remainder of the day and ideally for the following 24 hours to allow your corneas to recover and for any early signs of irritation to become apparent.

Step 5: Monitor your eyes for 48 to 72 hours. Watch for redness, pain, increased light sensitivity, blurred vision, or a sensation of something in the eye. These symptoms can appear several days after exposure in the case of Acanthamoeba and should never be ignored.

If any of the above symptoms develop after swimming with contact lenses, contact your optician or GP promptly. Do not wait to see if they resolve on their own. Early diagnosis and treatment of Acanthamoeba keratitis is critical for the best outcome.

What About Coloured Contact Lenses and Swimming?

This question is rarely addressed in mainstream eye care guides, but it is one that many Bella wearers ask during the summer months. Coloured contact lenses carry exactly the same infection risks as clear soft lenses when exposed to water. The pigment in the lens does not create additional risk, but it does not offer additional protection either. The lens material is equally porous, and Acanthamoeba does not distinguish between a clear and a coloured lens as a host. For a detailed look at how coloured lens materials work and what makes them safe when used correctly, see our guide on daily coloured contact lens wear.

The practical consideration for coloured lens wearers is that these lenses are often worn in the exact settings where water exposure is most likely: beach days, summer parties, outdoor pools, and holidays. This makes it especially worth planning ahead. If you are wearing monthly coloured lenses and plan to spend time near water, the safest approach is to remove them before swimming and avoid any water getting into your eyes while wearing them. If you want clear vision and the option of a coloured look on a day that involves swimming, switching to daily coloured disposables for that occasion is the most sensible choice.

Bella's Daily Collection includes soft coloured lenses ideal for one-off occasions where convenience and eye safety both matter: Bella Daily Contact Lenses.

Alternatives to Swimming with Contact Lenses

If you swim regularly, wearing contact lenses in the water is not a sustainable approach to vision correction regardless of how carefully you manage the risks. The alternatives below are genuinely effective and worth considering based on how often you swim and what you need in the water. For guidance on choosing the right lens type for your overall lifestyle, our guide on how often to replace your contact lenses provides useful context on replacement schedules.

Prescription swim goggles are the gold standard for regular swimmers who need vision correction. They eliminate all water contact with the eye, require no contact lens care routine on swim days, and are available for most standard prescriptions. Daily disposables with sealed goggles remain the most practical option for occasional swimmers who prefer not to invest in prescription goggles. Orthokeratology, which uses specially designed overnight lenses to temporarily reshape the cornea, is worth exploring with a specialist optician if you are a committed swimmer with myopia.

Final Thoughts

The core message from UK eye care bodies is straightforward: remove your contact lenses before any water activity whenever you can. When that is not possible, daily disposables and sealed goggles are the most practical risk-reduction strategy available. For coloured lens wearers especially, planning ahead means you can enjoy beach and pool occasions fully without compromising the eye health that makes wearing contact lenses possible in the first place.

See more: How Often Should You Replace Your Contact Lenses?