Which Brands Run Large and Which Run Small? A Realistic Guide to Fashion Sizing

We’ve all been there. You order a dress in your usual size, only to find it feels two sizes too small. Or you try on a coat in-store, expecting a snug fit—and it practically swallows you whole. The truth is, sizing is anything but standard across fashion brands, and it’s become one of the biggest frustrations in modern retail.

As someone who’s spent far too much time returning items that didn’t fit—and trying to decode sizing charts written in marketing speak—I finally turned to Tellar.co.uk to make sense of it all.

But before we get into tools and solutions, let’s look at the facts. Which brands run small? Which run large? And why is it so hard to get it right the first time?

Here’s your guide to brands that consistently size down or up, plus how to shop smarter in a fashion world with no universal sizing.

Why Brand Sizing Is So Inconsistent

Fashion brands don’t follow a shared sizing system. Instead, each uses proprietary fit models and demographic data to develop their size blocks. These decisions are influenced by:

Target customer age and shape
Fabric types (stretch vs rigid)
Country of origin (UK, US, EU, Asia)
Cultural fit preferences (slim vs relaxed)
Vanity sizing strategies

This means a UK 10 in one brand may be closer to a UK 8—or even a 12—in another. You simply can’t assume consistency.

Brands That Run Small

These brands are notorious for slim fits, narrow cuts, and minimal stretch. If you’re in between sizes, you’ll likely need to size up.

Zara (EU)

Zara is a high-street fashion powerhouse, but its sizing is famously unpredictable. In general, Zara runs small, especially in:

Blazers (narrow shoulders)
Trousers (tight on hips)
Tops and dresses (can run short in the torso)

Their fitted silhouettes and trend-led tailoring mean you’ll often need to size up from your standard UK fit.

🟩 Find your exact Zara size on Tellar

Reformation (US)

Reformation is known for its eco-conscious ethos and flattering cuts—but be warned: the sizing runs small, especially in bust and waist.

Their fitted dresses often require you to size up if you have a fuller chest or broader ribcage.

Urban Outfitters (US/UK)

Urban Outfitters often runs small across their own-brand lines (e.g., Out From Under, BDG), particularly in jeans, mini dresses, and bodycon styles.

Maje & Sandro (French)

Both of these French labels skew toward the European market, with a narrow, tailored fit. French sizing often assumes a leaner frame, so UK customers frequently need to go one size up—especially in structured jackets or trousers.

Weekday (Swedish)

Though Weekday markets itself as gender-neutral and relaxed, its denim and structured tops tend to run small, especially for curvier body types.

Brands That Run Large

These brands often favour looser silhouettes, generous fits, or oversized styling. You might need to size down—or at least try both options.

COS (Swedish)

COS is known for minimalist, architectural fashion—and intentional oversizing. Shirts, trousers, and jackets often come with extra volume. Unless you want the full oversized look, consider sizing down.

🟩 Tellar helps you size accurately in COS—based on how you like it to fit

Arket (Swedish)

Another minimalist Scandi brand, Arket typically runs larger in fit, especially across unstructured tops and knitwear. Their relaxed tailoring means a Medium often feels like a UK 12–14.

H&M (Global)

H&M sizing can be inconsistent, but many of their core lines (especially basics, knitwear, and outerwear) run slightly large, particularly in looser cuts.

However, beware—some of their trend lines (Divided, for example) swing the other way and run small. Confusing, we know.

Whistles (UK)

Whistles has a more generous cut than most UK high street brands. Dresses, trousers, and blouses tend to be more forgiving around the waist and hips. Most customers find they can size down comfortably.

White Stuff (UK)

Known for comfort and easy layering, White Stuff tends to run large—especially in tunic-style tops, jumpers, and relaxed dresses. Some shoppers size down one, occasionally even two sizes depending on the fabric.

🟩 Check your size in White Stuff using Tellar

Everlane (US)

Everlane offers clean, minimal basics with a relaxed ethos. Their shirts and trousers often fit a half-size up, and they provide sizing notes on each product page. Still, many find their usual UK size feels loose.

The Most Inconsistent Brands

Some brands just can’t make up their mind. You’ll be one size in tops, a different one in trousers, and completely lost when it comes to dresses. If you regularly shop these brands, check your fit every time:

ASOS – Varies wildly between their own-brand lines (ASOS DESIGN vs ASOS Luxe vs Collusion)
Free People – Often oversized in tops, tiny in shorts
Anthropologie – Different designers under one label = multiple sizing systems
Bershka / Stradivarius – Trendy Spanish brands that often run small, especially in waistbands
Topshop (via ASOS) – Denim fits true to size; tops often run tight

Men’s Brands That Run Small or Large

While women's sizing is notoriously inconsistent, menswear has its quirks too.

Brands That Run Small:

AllSaints – Slim fits across shirts and jackets
Uniqlo – Japanese sizing often runs small for UK men
Topman – Trend-led fits are often tighter in shoulders and thighs

Brands That Run Large:

COS Men’s – Similar oversized silhouettes as the women's line
M&S Menswear – Classic British sizing = generous across chest and waist
Charles Tyrwhitt – Shirts designed with comfort in mind; many size down

🟩 Tellar supports both women’s and men’s sizing—across fashion, basics, and tailoring

What I’ve Learned From Trying (and Returning) So Much

After years of trial and error, here’s my golden rule:

Always check sizing per brand—not per label.

And now, I don’t do that manually. I use Tellar.co.uk.

It lets you enter your actual measurements, or even just say “I wear Medium in Zara”
It instantly shows you your size across 1,500+ brands, including luxury, high street, and online-only labels
It’s completely free and requires just a one-time email login
You can even download their printable measuring tape if you don’t have one

🟩 Create your free profile

🟩 Find your fit before you shop

Final Thoughts: Size Doesn’t Equal Fit

When you find a piece you love, the number on the label shouldn’t be the thing that makes or breaks it. But the reality is—fit determines confidence, and size confusion can ruin even the most beautiful garment.

Knowing which brands run small or large gives you a head start. But combining that with your exact measurements—and a tool like Tellar—means you’re finally shopping from a place of clarity, not guesswork.

Stay Connected with Tellar

Follow Tellar.co.uk for sizing tips, brand breakdowns, and trend insights:

Tellar.co.uk – Find your size in 1,500+ brands real-time. It’s Free & Easy.