How Does Sizing Vary by Store for Jeans

Jeans sizing varies wildly by store because there's no regulated industry standard—brands create their own fit models, apply vanity sizing, and use different measurements, meaning a size 28 at one shop can fit completely differently at another. If you've ever walked out of a changing room frustrated because your "usual size" didn't fit, you're not alone, and I'm here to explain exactly why this happens and how to navigate it.

Why Jeans Sizing Is So Inconsistent

The brutal truth? Jeans sizing is a complete minefield. Unlike shoe sizes, which generally follow consistent measurements, clothing sizes—particularly jeans—have zero legal regulation. Each brand decides what a size 10 or a 28-inch waist means based on their own fit models, target demographic, and frankly, their marketing strategy.

Vanity sizing is the biggest culprit. Brands deliberately label larger garments with smaller sizes to make customers feel better about themselves. A study found that high street jeans often fit 1-2 inches larger than their stated waist measurement. So that "28-inch waist" jean might actually measure 30 inches. It's designed to boost your confidence and encourage repeat purchases, but it creates chaos when shopping across multiple brands.

Then there's the cut factor. A 28-inch waist in a high-rise style fits smaller than the same measurement in a low-rise jean because of where it sits on your body. Add stretch fabric into the mix—jeans with 1-3% elastane can stretch up to 1.5 inches with wear—and you've got a recipe for sizing confusion.

How Different Brands Actually Fit

From my years as a stylist, I can tell you that certain brands consistently run large, small, or true to size. Zara is notorious for running smaller than UK standard, particularly in their denim and tailoring—expect to size up at least once, sometimes twice. Their European-inspired fits are cut slimmer through the hips and thighs.

H&M tends to run true to size with their denim, though their compositions are softer and stretchier than premium brands. I find their Wide High Jeans particularly reliable. M&S, on the other hand, runs generously—many customers size down in their casualwear. However, their Magic Shaping range is brilliant for providing structure whilst being forgiving on the waist.

Mango runs slim, especially across the shoulders and hips. If you're between sizes, always go up. ASOS is tricky because they stock both their own label and third-party brands. ASOS Design generally runs true to size or slightly large, but always check individual brand size charts.

Reiss offers premium denim that's cut for a more tailored, European fit—expect sizes to run smaller. Whistles similarly leans towards a slimmer cut, though their quality justifies the premium price point. For a more generous fit, Monsoon runs large through the bust and waist, making it ideal if you prefer looser silhouettes.

Premium Brands Worth Investing In

If you're ready to invest, Arket offers exceptional quality with true-to-size fitting in most styles, though their cult Jade jeans run small—I'd recommend sizing up for comfort. The denim quality rivals brands twice the price. COS is another H&M group gem that offers sophisticated cuts with reliable sizing, particularly their Arch style which fashion editors swear by.

Levi's remains the gold standard, using waist and length measurements (W28 L30, for example) which should be more accurate—though even they vary between styles like the 501s versus the Ribcage. At 5'2", I always opt for their 27-inch length.

For independent brands, Albaray has become an influencer favourite with their mid-rise turn-up jeans cut from dull blue denim. The roomy straight fit is perfect for showing off shoes whilst maintaining that effortlessly chic aesthetic. Nobody's Child might be known for summer dresses, but their turn-up jeans in mid-wash hues offer a flattering fitted waist with a flare at the leg—brilliant quality for the price point.

Luxury Options That Deliver on Fit

When it comes to luxury denim, you're paying for precision. Citizens of Humanity offers the cult Ayla jean—loose and slouchy but slimmer at the hips for the most flattering fit. Their Creative Director recommends wearing them baggy (true to size) or sizing down to wear higher on the hip. The brand's attention to fit across global markets means you're getting a thoroughly tested product.

AGOLDE creates the '90s Pinch Waist—their best-selling style with a flattering high-rise waist and close fit through the hips. However, they run small, so stick to your true size or even size down as you want that close-fitting, flattering hug. Good American, co-founded by Khloé Kardashian, champions size inclusivity with their Always Fits jeans that mould to fit up to four different sizes thanks to innovative stretch denim.

Reformation makes the Cary jean, which editors consistently praise for balancing curvier figures. If you're larger on bottom than top with long legs, this style is worth every penny. DL1961 takes a forensic approach to fit, owning their own factory to ensure every detail is perfect—their Hepburn wide-leg is particularly brilliant.

My Professional Styling Tips

Always measure yourself properly: wrap tape around your natural waist (the narrowest point), hips (the fullest part), and inseam (crotch to ankle). Use these measurements rather than relying on size labels. For body shape considerations, hourglass figures should look for high-rise jeans with stretch to avoid gapping waistbands. Pear shapes benefit from bootcut or straight-leg styles. Apple shapes suit mid-rise with wide waistbands. Athletic or rectangle builds can add shape with boyfriend or barrel-leg styles.

Rise matters enormously. High-rise jeans sitting at your natural waist will feel tighter than low-rise at the same waist measurement. Fabric composition changes everything—100% cotton rigid denim needs sizing up compared to stretch versions. Read reviews obsessively before buying online. Other customers' experiences with sizing are invaluable, particularly noting whether they sized up or down.

Stop Guessing—Let Tellar Match You Perfectly

Here's the solution I recommend to every client: stop battling inconsistent sizing and use Tellar.co.uk, the UK's leading sizing tool. It matches your body exactly to over 1,500 brands instantly, so you never have to look at another confusing size guide.

Simply measure once using your bust, waist, and hip measurements—or input your existing brand size from jeans that fit you perfectly. Then use Tellar's Store Size Lookup tool to get your precise size in any brand, whether that's Zara, Reiss, COS, Arket, Levi's, or hundreds more. It's completely free, works in-browser with no downloads needed, and eliminates the guesswork entirely.

Plus, the Tellar Fashion Hub is packed with free posts from top stylists covering every fashion query imaginable. Honest, unbiased, independent advice—always free. For comprehensive guidance, check out The Ultimate Clothing Sizing Guide, discover Jeans Trends 2026, or explore the Ultimate Guide to Dresses & Best Buys and Ultimate Guide to Jackets & Best Buys.

Jeans shopping doesn't have to be a nightmare. Armed with the right knowledge about how brands fit, your accurate measurements, and Tellar's intelligent sizing tool, you'll find your perfect pair faster than ever. No more changing room disappointments, no more returns, just jeans that actually fit first time.