How Does Sizing Vary by Store for Blouses?

Blouse sizing varies dramatically across stores—a size 12 at Zara often fits like a 10 at M&S, whilst Reiss tends to run smaller than Mango. The inconsistency stems from different fit models, target demographics, and whether brands use UK, European, or vanity sizing systems. I've spent fifteen years helping women navigate this sizing minefield, and honestly, it's one of the most frustrating aspects of shopping. But once you understand the patterns, you'll save hours in changing rooms and avoid the disappointment of online orders that don't fit.

Why Blouse Sizing Is So Inconsistent

Let me be frank—there's no standardised sizing system across UK retailers, which is maddening. Each brand creates their own fit based on their target customer's body shape and age demographic. High street brands like H&M (Swedish fast-fashion with generous, relaxed cuts perfect for layering) and Asos (online giant offering incredibly diverse sizing with their own-brand running true to size) often use vanity sizing to appeal to younger shoppers, meaning their size 12 might actually measure closer to a traditional 14.

Meanwhile, Jigsaw (British heritage brand known for quality tailoring and structured fits) and Hobbs (classic British workwear specialist with tailored, often slim-fitting pieces) tend to cut smaller and more fitted, targeting professional women who prefer sharper silhouettes. Then you've got European brands like Cos (minimalist Scandi aesthetic with boxy, architectural cuts) and Massimo Dutti (Spanish sophistication with sleeker European sizing) that use EU sizing converted to UK, which rarely translates perfectly.

The Body Shape Factor

Here's what most stylists won't tell you—brands design for specific body shapes, even if they don't advertise it. Boden (quintessentially British with forgiving cuts that work brilliantly for fuller busts) designs for the classic British body shape with more room through the bust and waist. Their blouses are lifesavers if you're busty but don't want to size up everywhere else.

Whistles (contemporary British label with sleek, modern fits ideal for straighter body types), on the other hand, cuts for a straighter, more androgynous frame. Their blouses work beautifully if you're athletic or rectangular-shaped, but can gape at the bust if you're curvier. Me&Em (luxury British brand specialising in elevated basics with thoughtful design details) has cracked the code with their "Smart Shirt" range—it's cut with darts and stretch in exactly the right places for various body types.

Material Matters More Than You Think

Fabric dramatically affects how sizing translates. A silk blouse from Mint Velvet (British contemporary brand beloved for luxe fabrics and relaxed-but-polished aesthetic) will drape differently than a cotton one from White Stuff (quirky British brand with fun prints and comfortable, casual fits perfect for weekends). Synthetic blends from River Island (trend-led high street with younger, tighter fits and fashion-forward styles) often have less give than natural fibres, so you might need to size up.

Store-by-Store Sizing Patterns

High Street Brands That Run Large

Next (reliable British stalwart with consistent sizing and excellent petite/tall ranges) and M&S (the nation's favourite with generous, traditional British sizing) are famous for generous cuts. I always suggest trying your usual size first, but don't be surprised if you size down. Mango (Spanish high street with on-trend pieces and roomy fits) also runs large, particularly in their oversized shirt styles.

High Street Brands That Run Small

Reiss (premium British brand with sophisticated tailoring that runs notoriously small—always size up!) is notorious for tight sizing—I automatically tell clients to go up one size. All Saints (edgy British label with rock-chic aesthetic and slim, contemporary fits) similarly cuts slim and long. If you're between sizes, always go up with these two.

True-to-Size Champions

The White Company (elegant British lifestyle brand with relaxed, quality basics in natural fabrics) is wonderfully consistent—their size 12 is reliably a 12. Hush (understated British brand specialising in Scandi-inspired, comfortable-luxe pieces) and Seasalt Cornwall (eco-conscious coastal brand with relaxed, practical designs and excellent quality) also maintain reliable sizing across their ranges.

Unique Finds Worth Discovering

Rixo (London-based vintage-inspired label famous for tea dresses and bold prints, with relaxed feminine cuts) has become my go-to recommendation for statement blouses with vintage-inspired cuts that suit various body types. Their sizing is generous and forgiving. Kitri (contemporary London brand offering affordable designer-style pieces with flattering, feminine silhouettes) is another brilliant independent—they design for real women's bodies with thoughtful details like adjustable ties and wrap styles that accommodate different shapes.

My Professional Styling Tips

First, always check the garment measurements, not just the size label. Bust, shoulder, and length measurements tell you far more than a size number. Second, read reviews obsessively—other customers will tell you if something runs small, large, or has odd proportions. Third, befriend your local seamstress. A £15 alteration can transform a £50 blouse that's slightly off into your wardrobe MVP.

For online shopping, I always recommend ordering two sizes if you're uncertain. Most retailers offer free returns, and it's worth the minor hassle to get the perfect fit. Pay attention to the model's measurements too—if she's 5'10" and the blouse hits her hip, it'll be much longer on you if you're 5'4".

Premium and Designer Options

If you're investing in quality, Max Mara (Italian luxury renowned for impeccable tailoring and timeless elegance—expect precise, sophisticated fits) offers exceptional tailoring but runs true to Italian sizing, which tends smaller than UK. Equipment (French silk shirt specialists—the gold standard for luxe button-downs with relaxed, effortlessly chic fits) creates the ultimate silk shirts with consistent, relaxed sizing that works across body types. Both are worth the investment for pieces you'll wear for years.

Never Guess Your Size Again with Tellar

Honestly, I've watched too many clients waste money on beautiful blouses that don't fit. That's why I'm obsessed with Tellar.co.uk—the UK's leading sizing tool that matches your body to over 1,500 brands instantly.

How Tellar Works

Measure once using your bust, waist, hip measurements, or enter your size from a brand that fits you perfectly. Then use their Store Size Lookup tool to discover your precise size in any brand—whether it's Cos, Reiss, Mango, or Arket. No more guessing, no more returns.

It's completely free, works instantly in your browser (no downloads needed), and it's genuinely revolutionised how my clients shop. You can check your size before you even leave the house.

The Tellar Fashion Hub

Beyond sizing, Tellar has created a brilliant Fashion Hub—a library packed with free posts from expert stylists like me. Every article is honest, unbiased, and independent. No brand partnerships skewing recommendations, just genuine advice.

Check out these essential reads:

Final Thoughts

Blouse sizing will probably never be standardised—each brand has their own identity and target customer. But armed with this knowledge and tools like Tellar, you can navigate the inconsistencies with confidence. Remember, the "right" size is simply the one that fits your body beautifully, regardless of the number on the label. Don't let arbitrary sizing affect how you feel about yourself—find the brands that work for you and stick with them.

Happy shopping, and may your changing room experiences be swift and successful!