Mountain vista at sunset, showing the beauty of Vermont

We aim to improve the well-being of our community by locally designing and manufacturing the most comfortable, durable, best fitting socks while continuously reducing our environmental impacts.

We are a sock company, and we don’t believe we can be a positive force for our community – or claim to be socially responsible – without committing to environmental responsibility, too.

For us, that commitment begins with durability, one of our primary design principles. Fundamentally, sustainability is a design decision that requires a commitment to continuous improvement and innovation. By designing for durability, we don’t simply ensure that our products perform better, last longer, and hold up to our Unconditional Lifetime Guarantee. To us, making a more durable product is a hallmark of buying less and keeping textiles out of landfill, and it’s one of the best ways to minimize the usage of raw materials we rely on.

When we dug deeply into our environmental footprint – despite decades of effort to operate more responsibly – we discovered some challenging truths about our industry, our materials, and our own manufacturing. Today, every sock we make has an impact on the planet, and there’s a lot we haven’t figured out yet, but we’re learning every day. We ask that you continue to hold us to the high standards we’ve historically set for ourselves, and as we address the challenges ahead, we’ll relay the actions we’re taking to forge a more responsible path that doesn’t compromise people or the planet.

Materials in Our Socks

Stacks of the Number 2 Merino Wool hiking socks in blue and gray

Every material we use in our socks has been carefully chosen and tested to meet our rigorous durability standards. We currently use natural and synthetic fibers, and only 3 types of fiber per sock. As you’d expect, we are actively investigating and testing new fibers and yarn blends that do not appear in our current products.

We’ve prioritized Merino Wool throughout our product lines and our goal of producing the most responsibly made product is reflected in our commitment to the success of the Responsible Wool Standard.

Merino Wool

What We Use

Merino Wool is nature’s most incredible high-performance fiber. It’s breathable, durable, thermoregulating, moisture wicking, odor resistant, and renewable, too.

For many years we’ve prioritized the sourcing of Merino Wool exclusively from sheep that have not been exposed to the practice of mulesing. In early 2019 we made a commitment to support the Responsible Wool Standard (RWS) and work toward shifting 100% of our wool supply to RWS-certified Merino Wool.

RWS is a voluntary standard managed by the Textile Exchange with strict guidelines to protect animal welfare and adhere to progressive, sustainable farm and land management practices while maintaining traceability throughout the entire supply chain.

Where We're Going

Shifting our material base to 100% RWS-certified wool is a big endeavor for us, and it requires that we use the remaining non-RWS wool we have in inventory before we can say – and certify – that 100% of the wool we use in our products is RWS-certified. We're still on the journey to making this happen, and our commitment remains. We don't mean to sound vague, we just don't want to make false promises as we learn and progress. Our preference for Merino Wool and our commitment to RWS means the success of the Responsible Wool Standard is very important to us.


What We Use

Nylon is an incredibly strong, durable, lightweight, moisture-wicking synthetic fiber and are critical in our products.

Similar to our shift to RWS wool, we're in the process of shifting our nylon inventory to as much recycled nylon as possible. We currently use REPREVE®, a nylon 6 fiber made from pre-consumer industrial waste that would otherwise be landfilled or downcycled. Using REPREVE® instead of virgin nylon allows us to offset the use of crude oil, benzene, cyclohexane, and other harmful hydrocarbons that are involved in the production of virgin fiber. In short, using recycled nylon conserves energy and water and reduces greenhouse gas emissions from manufacturing. We aim to reduce our use of virgin nylon in our products and have increased our use of recycled nylon year over year towards that goal.

Where We're Going

Our goal is to reduce and phase out the use of virgin, petroleum-based fibers. We are currently working with our suppliers to source recycled and renewable alternatives, and we're testing multiple options to ensure they meet our durability requirements and can be incorporated into all our product lines.

To date, nylons generated from pre-consumer waste material have held up well against our durability requirements, but we’d like to find an equally good source of post-consumer recycled nylon or yarns that blend both pre- and post-consumer nylon.

Spandex / Elastane

What We Use

We use Lycra® Spandex to provide elasticity, strength, and form-fitting comfort. Like conventional nylon, spandex is derived from petroleum and has been important to the performance of our products. Unfortunately, it’s the most difficult material in our fiber mix to replace with a recycled alternative.

Where We're Going

When it comes to synthetics, we’re primarily focused on converting virgin nylon and polyester to recycled alternatives. However, we’re also looking for functional, recycled spandex alternatives.


What We Use

We use Coolmax® and Thermolite® polyester fibers in combination with nylon and elastane to provide customers with tough, high-performance, moisture-wicking socks that don’t contain Merino Wool. 

Where We're Going

Although virgin polyester represents a minor percentage of our fiber mix, we aim to replace it with a recycled alternative. Recycled polyester is widely available and its use would lessen our dependence on petroleum as a raw material source for our yarns while reducing greenhouse gas emissions.

Other Materials

Sock Packaging

The socks you purchase at retail or order from us directly come packaged in recycled FSC-certified paper that’s printed with water-soluble glues and vegetable-based inks.

eCommerce Shipping Boxes

In 2019 we transitioned our ecommerce shipping boxes from 83% post-consumer recycled cardboard to 100% post-consumer recycled cardboard. We also continue to test and pilot new shipping options, most recently including compostable bags. 


In 2019 we initiated efforts to reduce and eliminate our use of polybags, which we’ve historically used to protect our product when shipping to our retail customers. Polybags end up in landfills and aquatic environments, contributing to a range of downstream environmental and health problems, as they take hundreds of years to break down. 

After substantial research, testing, and conversations with various stakeholders, we will phase out our use of polybags and shift to recyclable, post-consumer paper bands. This is an ongoing process here at Darn Tough, and we still use some polybags. 


In Our Products

All of our suppliers provide us with yarns that meet or exceed rigorous chemical testing standards and the requirements for California Proposition 65. This means our materials have been independently tested for regulated and non-regulated substances and have been approved as harmless to human health. Additionally, we regularly test our products with certified 3rd party labs as an extra precaution to provide additional assurances to our customers that our final product adheres to strict chemical safety requirements.

We are frequently asked if our products are bluesign®-certified, which is another rigorous standard that reviews each step in the supply chain to approve chemicals, materials, processes, and products to ensure environmental, worker, and consumer safety. While our large suppliers are bluesign®-certified, a number of our small and family-owned suppliers are not, primarily because they can’t afford the high certification costs. Rather than allow that to stall our progress, we’ve moved ahead with a Restricted Substances List (RSL) that is based on chemistries and criteria set forth by bluesign® and the Zero Discharge of Hazardous Chemicals (ZDHC) list. This RSL provides additional assurances to our customers that we are adhering to the safest, most benign chemistries in our industry.

In Our Manufacturing Processes

At the end of 2019 we decommissioned washers used in our finishing operations and replaced them with steam dryers, reducing our water usage by more than 90%. Historically, we used 1 cup of 12% sodium hypochlorite (bleach) once a month to clean each of the washers, so removing the washers from our finishing operations eliminated our need for this chemical, which was previously the most toxic chemical solution left in our manufacturing operations.

We are Darn Tough Vermont, and we know our success depends on the health of our community, the health of the environment, and our efforts to improve both. We invite you to come back here for updates as we accelerate progress on our programs and products.