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Heatwave Thermalwear

2 Pack Women’s Thermal Long Janes Base Layer Pants Warm Winter Underwear Bottoms for Outdoor Hiking & Skiing by Heatwave Thermalwear

Regular price £6.67 GBP
Regular price Sale price £6.67 GBP
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Meet the 2 Pack Women’s Thermal Long Janes Base Layer Pants by Heatwave Thermalwear—your cold-weather essential for active days and cosy nights. Designed to lock in warmth without bulk, these breathable cotton thermals deliver flexible comfort under jeans, ski gear, or workwear. A customer favorite for winter layering, they combine soft-touch fabric, reliable insulation, and a flattering, stay-put fit—making them a smart, value-packed choice for hiking, skiing, camping, commuting, and relaxing at home.

Key Feature 1: Warm Winter Protection

Description: Engineered for cold-weather performance, these thermal long johns are crafted to retain body heat and provide effective insulation. The lightweight design makes them ideal for layering, offering dependable warmth under everyday outfits or technical outerwear—without adding uncomfortable bulk.

Benefits: Keeps you comfortably warm during outdoor adventures and daily commutes. Ideal for hiking, skiing, camping, and indoor lounging. Low-bulk construction ensures a smooth fit under trousers, jeans, and uniforms.

Key Feature 2: Soft Cotton Fabric

Description: Made from premium natural fibres for breathable, all-day comfort. Composition: Cotton and polyester mix. The fabric helps regulate temperature and wicks away moisture so you feel cosy, dry, and fresh throughout the day.

Benefits: Skin-friendly softness that won’t irritate sensitive skin. Breathable warmth that prevents overheating during active wear. Durable construction designed for repeated washes and everyday use.

Key Feature 3: Comfortable Fit & Flexibility

Description: A stretchable construction and elasticated waistband provide a secure, flexible fit that moves with your body. The smooth, non-restrictive design sits discreetly under clothing without bunching, pinching, or riding up.

Benefits: Total freedom of movement for active days on the trail or slope. Flattering, stay-put fit ideal for layering and lounging. Comfort-first design that supports all-day wear.

Sizes

Each pack includes 2 pairs of women’s thermal long johns. Available sizes:

  • UK 10–12 (EU 38–40)
  • UK 14–16 (EU 42–44)
  • UK 18–20 (EU 46–48)
  • UK 22–24 (EU 50–52)

Designed to offer a secure, comfortable fit for every body shape.

Colours Or Style Options

  • Classic Black
  • Crisp White
  • Marl Grey

Timeless colours that coordinate effortlessly with ski layers, outdoor gear, and everyday winter outfits.

Care Guide

  • Machine washable at 40°C.
  • Wash with similar colours to maintain softness and long-lasting quality.

Why Choose This Product

Trusted brand: Heatwave Thermalwear is known for premium materials and reliable craftsmanship in essential winter apparel.

Outstanding value: Cost-effective 2-pack delivers superior warmth and comfort at a great price.

Everyday versatility: Perfect for work, travel, outdoor sports, and at-home comfort.

Effortless style: Classic colours that pair with anything in your winter wardrobe.

Customer favorite: A go-to base layer for women who want warmth, breathability, and a flattering fit.

Additional Information

Usability: Ideal under ski pants for extra insulation on the slopes, beneath hiking trousers for chilly trail days, under workwear for drafty environments, or as a cosy layer for evenings at home and weekend getaways.

Warranty and Support: Please refer to the retailer’s warranty, returns, and support policies for full details.

Shipping

We have partnered with 20 innovative grassroot companies that we believe can help reverse climate change. We allocate a fixed margin from every sale to support fund nature-based carbon removal solutions such as reforestation and soil carbon sequestration. Fund companies such as DroneSeed, Grassroots Carbon, and Pachama.

We are committed at Sock Stack to neutralize our shipping emissions and remove carbon dioxide from the atmosphere. Learn more here.

We also work closely with Royal Mail to ensure hassle-free, on-time delivery. Generally processing times are within 1 business day*. Processing times may also be extended during holidays, launches/re-stocks, limited edition releases and promotions. We will notify you as soon as your order ships or if we foresee any issues with fulfilling your order. Read our full Shipping Policy for more information.
*Please understand that business days do not include weekends and Bank Holidays (United Kingdom).

£3.95 flat fee for all domestic within the United Kingdom (free shipping over £22), 2-4 working days.
£5.95 express fee for all domestic within the United Kingdom, 1-3 working days.

Easy returns

Not completely satisfied with your purchase? Reach out within 35 days to explore hassle-free return options. We've simplified cancelations for a full refund and additionally return requests can be made from your online account. Please review our Refund Policy for more details. Thank you for your patience and understanding as we navigate this together.

Contact

Sock Stack does not have a call centre and we're not set up to handle high volumes of phone calls.

The Sock Stack brand was built online, including our customer support. Though you may receive an automated response every once in a while, all channels are manned by human staff who are eager to help you out, quickly and efficiently.

Thank you again for visiting Sock Stack. For information on our new product launches, please follow us on Instagram & Facebook. For customer service inquiries, please send us a message on Facebook Messenger or e-mail us at sockstack@outlook.com. For order inquiries, please include your order number for faster service.

Clearpay

Clearpay makes budgeting easier, allowing you to break down your payments into four installments, due every two weeks, interest free. Head over to Sock Stack and find something you love. Then, just add to bag and simply select Clearpay as your payment method at the checkout. Enjoy your new stuff right away and pay over four installments.

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Klarna

Buy now and pay 30 days later with KLARNA payment portal. You get all the “closure” of a full upfront payment, but with the cash-flow benefits of spreading the cost. The total amount charged to your card is no greater than if you simply paid for the entire purchase up front.

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Influencers

We are a young, bold homeware brand. We’re fun, we’re social and we’re an upcoming brand that doesn’t sleep. Interested in partnering? Apply today to be part of our community.

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Our Mission

Heatwave Thermalwear® envisions becoming the most celebrated, trustworthy, and sought-after brand by offering superior, distinctive, and inexpensive thermal wear products that exceed every customer's expectations. Heatwave Thermalwear's® vision is to become a leading thermal underwear baselayer brand by delivering the most refined and high-grade products to the customers that are thoughtfully developed to withstand extremely cold conditions while offering enhanced protection and unmatched comfort.

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Function, Fit & Style

Heatwave Thermalwear® strives to provide a diverse collection of the highest quality and affordable thermal underwear to men and women. Our thermal socks, long-sleeve base layers, long johns, hats and gloves are meticulously designed to be safe, lightweight, and breathable, providing fast-wicking and added warmth. As a customer-first brand, we are committed to fostering solid and lifelong relationships with our clients and aspire to deliver exceptional quality and value in our products.