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.





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

For many years we’ve prioritized the use 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 shift 100% of our wool supply to RWS-certified Merino Wool.

RWS is a voluntary standard 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.

When we made our RWS commitment, the standard was still relatively new and there weren’t many certified farms in the world. Initially, that meant it wasn’t possible for us to obtain RWS-certified yarns in all the sizes we required, so we were forced to simultaneously procure both non-RWS and RWS Merino wool.

Although the market share for RWS is only estimated at ~1% of global wool production, the number of certified sources has grown substantially over the last couple years. Today, 100% of the wool we procure is RWS-certified, with the majority of our supply coming from South Africa, New Zealand, Uruguay and Argentina.

Merino Wool is the most important and relied upon fiber in our products and accounted for 56% of our yarn consumption by weight last year.



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 set a goal of 2021, but faced new, if not unexpected challenges, and did not meet our goal. The commitment remains, and we are researching how we can get closer by close of 2022. 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; we’ll continue working with Textile Exchange to improve on the standard as we did over the last year for RWS 2.0.

Finally, wool represents a disproportionately large percentage of our carbon footprint relative to its contribution in our fiber mix. That’s predominantly due to enteric fermentation (sheep burp methane), as our suppliers employ the most rigorous environmental standards in the world. However, there are also meaningful carbon, chemical, and water expenditures associated with part of the finishing process – also known as “superwash” – that most of our wool is subjected to. The superwash treatment results in a soft, comfortable, machine-washable wool, whereas currently available alternatives feel drier and may compromise abrasion resistance or fail to provide the same long-lasting shrink resistance to washing. Ultimately, our goal is to reduce the impacts associated with the Merino wool we procure, and we are currently working with our suppliers to identify and test more environmentally friendly, RWS-certified alternatives into our products.


We 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. While we aim to reduce our use of virgin nylon in our products, recycled nylon only accounted for 4% of our nylon consumption last year.



We’re actively working with our suppliers to source more recycled nylon so we can incorporate it across 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.


Nylon is an incredibly strong, durable, lightweight, moisture-wicking synthetic fiber. Nylon yarns are critical in our products and comprised nearly 14% of our entire material consumption by weight last year.



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 of our product lines.  


We use Lycra® to provide elasticity, strength, and form-fitting comfort. While spandex accounts for no more than 5% of the fiber used in our finished product, it represented 27% of the raw materials we procured last year. 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.



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.


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. Last year, virgin polyester accounted for 2.5% of our material consumption by weight.  



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.


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

In 2019 we transitioned our ecommerce shipping boxes from 83% post-consumer recycled cardboard to 100% post-consumer recycled cardboard.

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.

The vast majority of material recovery facilities (MRFs) do not handle recycling for polybags despite the fact that the ones we’ve historically used are 100% recyclable low-density polyethylene (LDPE) and can technically be remade into film for new polybags or used as feedstock for durable products such as composite decking.

Unfortunately, polybags are very difficult for MRFs to handle so most polybags end up in landfills and aquatic environments where they take hundreds of years to break down and contribute to a range of downstream environmental and health problems.

Throughout 2019 we researched and tested multiple alternatives to polybags, including compostable polybags. Unfortunately, even the biodegradable/compostable polybags didn’t meet our standards, as their effects on aquatic environments were untested.

We also ran experiments to ship without the use of polybags and did not experience additional damage to our socks.

After substantial research, testing, and conversations with retail partners to identify suitable polybag alternatives that adhere to their handling and warehousing requirements, we plan to phase out polybags. In the absence of polybags, we’ll be shifting to recyclable, post-consumer paper bands, which helps reduce a major plastic waste stream for our retail partners. Socks we ship internationally will be transported in boxes that are lined with a single compostable polybag to prevent product damage that might otherwise occur during maritime transport.

Unfortunately, there are many large retailers who rely on polybags, and some of them have historically removed our polybags and re-packaged our socks in their own polybags. If those retailers are not simultaneously phasing out polybags in their operations over the next 12 months, customers might receive our socks in a polybag that was applied by that retailer.


All of our suppliers provide us with yarns that meet or exceed the Oeko-Tex® 100 Standard 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 new 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.



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.