The Warmest Socks, Gloves, Hats and Scarves Of 2019

by Justin Thomas •

Click here if you want to jump straight to my list of the warmest garments available.

I’ve been researching the warmest wool products available. Here’s what I discovered:

Qiviut (Musk Ox Down)

Qiviut (pronounced “kiv-ee-ute”) is the name for the downy hair of the musk ox. It is the warmest fiber in the world — about eight times as warm as sheep’s wool. It’s also an ultralight fiber. So it’s an extremely warm, very light and very soft fiber.

It’s also quite expensive — a pair of Qiviut socks will costs about $175.

Musk oxen live in Alaska and Canada where temperatures sometimes drop to –100ºF (-73ºC), so they need protection.

I’ve been testing Qiviut scarfs — and they are superlatively warm. Qiviut’s combination of intense warmth and ultralight hand is unique.

A single garment of it can make a significant difference on a frostbitten night.

In Alaska, qiviut is obtained from farmed animals or gathered from the wild during the molt. Unlike sheep, the musk ox are not sheared.

Yak Down


Similar to qiviut, yak down is a very warm fiber that’s also lightweight and soft. It’s a more affordable alternative to the rare qiviut.

Yaks are primarily raised by nomadic Tibetan and Mongolian families. Their wool is combed once per year in the springtime.

According to Kora, a yak performance wear company, yak fabric is 40% warmer merino wool. It has 66% greater air permeability and 17% greater water vapor permeability (tested with ASTM D1518, ASTM D737, ASTM E96).

Bison Down


Bison down is a very warm, insulating fibre. It is also very durable for such a soft fibre. It has a moisture regain of about 30%, compared to 18% for wool — this means that even when saturated, the fibre draws moisture away from one’s skin.

There is only a limited amount of fibre available – estimated at 10,000 pounds per year versus 2,100,000,000 pounds of sheep wool.

It is harvested in Colorado and South Dakota, as a by-product of the bison meat industry.

Alpaca Wool


AAlpaca wool is about three times as warm as sheep’s wool, and it is lightweight and durable. It contains no lanolin, which makes it hypoallergenic and odorless. Alpaca wool also has one of the highest moisture ‘wicking’ properties of all natural fibers.

Alpacas are kept in herds that graze in the mountains of Peru, Bolivia, Ecuador and Chile.

Other Wools

Wild Kashmiri goats Capra falconeri cashmiriensis roaming the Great Orme headland in Llandudno North Wales

Other warm (and very soft) wools include camel, angora, cashmere, vicuna and guanaco.

Durability and Fineness

In terms of durability, bison is in most cases the strongest, followed by qiviut and yak down, followed by alpaca and then merino.

In terms of fineness, any fiber that has a diameter of 20 µ (microns) or less will feel very soft to the touch. In the alpaca world, the labelled “royal” alpaca should indicate fibres under 19 µ, “baby” alpaca should indicate fibres that are around 22.5µ and “superfine” alpaca is 26µ. There’s also an International Alpaca Mark that indicates the fibre is less than 28 µ. In the merino world, look for wool labelled “ultrafine” (around 15-17 µ) or “superfine” (about 24 µ).

Here’s a list of fibers from finest to coarsest (in microns): Suri Alpaca (10 -15 µ), Qiviut (11-13 µ), Yak (15 – 19 µ), Huacava Alpaca (15 – 29 µ), Cashmere (15 – 18.5 µ), Ultrafine Merino (17 µ), Yak Down (17.5 to 19µ), Bison (18.5 µ), Superfine Merino (24 µ), Standard Wool (30 – 32 µ), Human Hair (60 – 80 µ).

Based on this criteria, these are the warmest woolens I could find:

Warmest Socks

Warmest Gloves

Warmest Hats

Warmest Scarves

Warmest Base Layers (Top)

Warmest Base Layer (Leggings)

Warmest Sweaters

Fiber Reference

Fleece & Fiber Sourcebook — this book explains the many types of animal fibers in the world