Sauna Hat Guide: Wool vs Felt, Sizing and Care

Why people wear one

Heat stratifies in a sauna: the air near the ceiling is much hotter than the air near the floor, and on the top bench your head sits in the hottest layer. A thick felt hat slows that heat on the way to your scalp and covers your hair, which is why sauna retailers sell them as a comfort item for the top bench.

Sellers commonly suggest dipping the hat in cool water before you go in. Finnmark describes a damp wool hat as cooling "by slow evaporation." A dry hat still insulates, just without the cooling.

Wool vs felt vs linen

Watch the word "felt" on a listing. It describes how the hat is made, not the fiber, so a "felt sauna hat" can be wool or polyester. If you want wool, look for "100% wool" in the description. Thin craft felt is a costume piece; you want felt thick enough to hold its shape.

Sizing

Nearly every sauna hat is one size. Finnmark lists its traditional wool hat at about 27 × 30 cm, and Emendo says its felt hat fits head circumferences from 52 to 64 cm (about 20.5 to 25 inches). Wool felt can shrink with hot washing, so buy a hat that is comfortable now, not snug.

Care

• Wool felt: rinse in cool water after use, hand wash gently (one maker says no warmer than 30°C, 86°F), and air dry. No dryer.
• Polyester felt: same routine; it dries faster.
• Cotton blends: Rento lists a 40°C (104°F) machine wash. It says not to bleach or tumble dry.
• Hang it to dry between sessions so it doesn't stay damp in a gym bag.

Where to buy

Sauna retailers like Finnmark list prices and materials plainly, which makes them a useful reference. On Amazon, search by material so you get the kind you want: wool sauna hats, felt sauna hats or linen sauna hats. Check the listing says 100% wool if that is what you want, and look for a stated size if your head is larger than average.

Common questions

Why wear a sauna hat?

Comfort. Hot air rises, so the air at head height on the upper bench is the hottest in the room. A felt hat slows that heat on the way to your scalp and hair. Retailers like Finnmark suggest soaking it in cool water first, so it cools as it dries.

Is a wool or felt sauna hat better?

"Felt" is how the hat is made; wool is one fiber it can be made from. A wool felt hat is the traditional choice and the thickest. A polyester felt hat looks similar, costs less (Finnmark lists them at $9.99 against $13.99 to $19.99 for 100% wool) and dries faster.

How do you wash a sauna hat?

Hand wash it in cool water and let it air dry. Finnmark's wool hats say hand wash gently and air dry, and one maker sets the limit at 30°C (86°F). Hot water and a dryer can shrink wool felt. Cotton blend hats are sturdier: Rento lists a 40°C machine wash with no tumble drying.

What size sauna hat do I need?

Most are one size. Finnmark lists its traditional wool hat at about 27 × 30 cm, and Emendo says its felt hat fits head circumferences from 52 to 64 cm. If you are outside that range, look for a brand that publishes the circumference.

Do you wear a sauna hat in an infrared sauna?

You can, but there is less reason to. An infrared cabin runs cooler, about 145°F for Sun Home's Solstice 2, and heats you with panels rather than hot air at the ceiling. Hats are mostly worn in traditional saunas.