Best Sun Hats for Snorkeling: Complete Buyer’s Guide

Finding the right sun hat for snorkeling is harder than it sounds. Most sun hats are designed for dry land — they blow off the moment you put your face in the water. Swim caps designed for pools offer no UV protection at all. The product you actually need sits squarely between the two: a UPF-rated hat that stays on underwater.

This guide covers exactly what to look for and which options work best for different snorkeling styles.

What Makes a Good Snorkeling Sun Hat

UPF 50+ Rating

UPF (Ultraviolet Protection Factor) is the fabric equivalent of SPF. UPF 50+ fabric blocks 98% of UV radiation — the same protection standard used by dermatologists for high-risk sun exposure. Any snorkeling hat worth considering should carry a UPF 50+ rating. This is non-negotiable given that water reflects up to 50% of UV back at you while snorkeling.

Secure Fit That Works Underwater

This is where most sun hats fail for snorkeling. A hat that works on the beach will float off the moment you dive below the surface. Look for an adjustable design with a snug but comfortable band that stays put through head movement, currents, and diving. All Nammu hats use an adjustable design specifically engineered for in-water security.

Coverage Area

Consider which areas you most need to protect:

• Scalp and neck only: A standard swim hat without visor or ear flaps provides good baseline coverage
• Scalp, neck, and ears: Ear flaps add coverage for the ears, which are highly UV-exposed during snorkeling
• Scalp, neck, ears, and face: A visor adds forehead and face shade — best for long sessions or very high UV environments

Material and Comfort

The best snorkeling sun hats use nylon-spandex blends that are lightweight, quick-drying, and flexible enough to move with your head. Avoid stiff materials that create pressure points during extended wear. Nammu hats are made from 80% nylon and 20% spandex — chosen specifically for in-water comfort and UPF performance.

Which Nammu Hat Is Right for You

For Most Snorkelers: EX UV Pro with Ear Flap

The EX UV Pro with Ear Flap is our most popular snorkeling hat. The square back provides more neck coverage than a standard hat, the ear flaps protect the ears from UV, and the secure fit works in currents and at depth. Rated 4.77 out of 5 from 22 reviews. Works with both traditional and full-face snorkel masks.

Best for: Galapagos, Maldives, Hawaii, Caribbean, Southeast Asia — any destination with high UV and extended snorkeling sessions.

For Maximum Coverage: EX UV Pro with Visor and Ear Flap

The EX UV Pro with Visor and Ear Flap adds a flexible brim to the ear flap model for full face and forehead shade. The most complete coverage available in our range.

Best for: Equatorial destinations, people who burn on the forehead and face, extended multi-hour sessions.

For Casual Snorkeling: Classic Nammu

The Classic Nammu is the right choice for casual snorkeling in moderate UV environments. Clean styling, secure fit, UPF 50+ coverage for the scalp and neck. Available in a wide range of colors and prints.

Best for: Resort snorkeling, Mediterranean holidays, moderate UV destinations, beginners.

For Kids: Classic Nammu in XS

All Nammu hats start at XS size — suitable for toddlers from age 2. The Classic Print version is particularly popular with children for the fun patterns and colors.

Size Guide

Getting the right size ensures the hat stays on underwater.

• XS: 44.5cm — best for babies and toddlers
• One Size: 54.6cm — fits most adults
• XL: 59.7cm — for above-average adult head sizes

Measure your head circumference just above your ears for the most accurate fit. Check the full Nammu sizing guide here.

Browse the full Nammu snorkeling hat collection →