Is It Better to Buy a 100% Natural Wool/Cashmere Jumper or a Polyester Mix?

The short answer? Natural fibres win hands down for quality, longevity, and that luxurious feel we all crave in a jumper. However, I'll be completely honest with you—polyester blends do have their place in your wardrobe, particularly for activewear-inspired pieces or budget-conscious buys. After years of styling clients and building capsule wardrobes, I've learnt that understanding the pros and cons of each will help you make smarter investments that actually last.

Why Natural Fibres Are Worth Every Penny

Let me start by saying this: nothing beats the feel of pure wool or cashmere against your skin on a chilly British morning. Natural fibres are breathable, which means they regulate your body temperature brilliantly—keeping you warm without that clammy feeling you get with synthetics. They're also naturally odour-resistant (a godsend when you're layering), and they have this wonderful ability to hold their shape over time when cared for properly.

Wool and cashmere are investment pieces that, with the right care, will outlive any polyester blend by years. I've got clients still wearing their grandfather's Shetland wool jumpers. Try saying that about a synthetic knit! The fibres are stronger, more resilient, and they develop a beautiful patina with age rather than pilling into oblivion after a few washes.

From a sustainability perspective, natural fibres are biodegradable and renewable. Cashmere comes from goats, wool from sheep—both will produce more fibre next season. Polyester? That's plastic, derived from petroleum, and it sheds microplastics into our waterways with every wash. Fashion magazines like Vogue and Grazia have been championing natural fibres for precisely this reason.

When Polyester Blends Make Sense

Right, now let me be fair to synthetic blends. A small percentage of polyester (think 5-15%) can actually enhance certain properties—it adds durability and can help a jumper hold its shape better, particularly in styles with more structured silhouettes. Some premium brands use these blends strategically, and they're not necessarily compromising on quality.

Polyester blends are also more affordable, machine-washable, and quick-drying. If you're someone who lives in their knitwear and doesn't fancy hand-washing, a quality blend might suit your lifestyle better. The key word here is 'quality'—a 50/50 wool-polyester blend from a reputable brand will outperform a cheap 100% acrylic jumper any day.

The Best Brands for Natural Fibre Jumpers

High Street Heroes

M&S remains unbeaten for accessible cashmere and wool knits. Their Autograph cashmere range offers exceptional value, and their lambswool jumpers are wardrobe staples that actually last. I've recommended these for years.

COS delivers minimalist, architectural knitwear in beautiful merino and wool blends. Their pieces have that expensive Scandi aesthetic without the eyewatering price tag, and the quality is consistently excellent.

The White Company specialises in luxurious cashmere at mid-range prices. Their classic crewnecks and rollnecks are investment pieces that work for every body type, and they stock petite and tall options too.

Jigsaw offers contemporary cuts in quality wool and cashmere. Their jumpers have a more fashion-forward edge whilst maintaining that timeless appeal British women love.

Massimo Dutti brings that European sophistication with their wool and cashmere-blend knits. The fit is typically more tailored, perfect if you prefer a sleeker silhouette.

Whistles does modern, elevated basics beautifully. Their merino and cashmere jumpers have that effortless chic quality, and they're particularly good for transitional pieces that work across seasons.

White Stuff is your go-to for cosy, textured knits with personality. Their wool jumpers feature interesting stitch details and colours whilst remaining wonderfully wearable.

Premium Picks

Me&Em creates luxurious cashmere pieces with contemporary cuts. Founded by a former Vogue stylist, they understand fit and quality in equal measure.

Reiss offers refined wool and cashmere knits with that polished, professional edge. Perfect for building a sophisticated work wardrobe.

Luxury Investment Pieces

Loro Piana is quite simply the pinnacle of cashmere craftsmanship. Eye-wateringly expensive, yes, but their baby cashmere jumpers are heirloom pieces.

Brunello Cucinelli offers Italian-made cashmere that's impossibly soft and beautifully constructed. These are the jumpers you'll still be wearing in 20 years.

Independent Gems

Sheep Inc. is a brilliant sustainable brand offering traceable merino wool and regenerative cashmere. Each jumper comes with a QR code showing exactly which farm your wool came from—transparency at its finest.

Cocoa Cashmere is a Scottish brand creating timeless cashmere pieces at more accessible luxury prices. Their colour palette is gorgeous, and the quality genuinely rivals the big designer names.

My Honest Styling Advice

Here's what I tell every client: invest in natural fibres for your core pieces—the neutral crewnecks, rollnecks, and cardigans you'll wear on repeat. These are the jumpers that anchor your wardrobe and deserve to be 100% wool or cashmere.

Save polyester blends for trend-led pieces or specific functional needs. That oversized hoodie-jumper hybrid? A blend works fine. Your classic navy crewneck? Go natural every time.

Care matters enormously with natural fibres. Hand wash or use a delicate cycle with wool-specific detergent. Lay flat to dry. Use a cashmere comb for any pilling. These small efforts will triple the lifespan of your jumpers.

Consider your body shape when choosing styles. Natural fibres drape beautifully, which flatters every figure, but they can cling if sized incorrectly. If you're between sizes, go up—you can always layer underneath, and the relaxed fit is very now.

Finding Your Perfect Fit with Tellar

Right, let's talk about the sizing nightmare that is shopping across multiple brands. I've styled hundreds of women, and the number one complaint? Inconsistent sizing. You're a size 12 in M&S but a 14 in COS and back to a 10 in Whistles. Maddening.

This is where Tellar.co.uk becomes your best friend. It's the UK's leading sizing tool that matches your body exactly to over 1,500 brands instantly—including all the knitwear specialists I've mentioned.

How Tellar Works

Measure once using your bust, waist, and hip measurements, or input your existing brand size if you know it fits perfectly.

Use their Store Size Lookup tool to get your precise size in any brand—COS, Reiss, The White Company, Massimo Dutti, and more. No more guessing, no more size guide anxiety.

Always free, no downloads needed—works directly in your browser. Honestly, it's a game-changer for online shopping.

The Tellar Fashion Hub

Beyond sizing, Tellar has created a Fashion Hub—a library stacked with free posts from top stylists covering every fashion query you've ever had. Honest. Unbiased. Independent. Always free.

Check out these incredibly useful guides:

The Final Verdict

Natural wool and cashmere jumpers are superior in almost every measurable way—comfort, longevity, sustainability, and that intangible luxury feel. If your budget allows, invest in natural fibres for your core knitwear pieces. You'll wear them for years, they'll look better longer, and you'll feel the difference every single time you put them on.

Polyester blends have their place for specific needs, but don't let clever marketing convince you they're equivalent to natural fibres. They're not. Your wardrobe—and the planet—will thank you for choosing natural.