What is Sizing Like at Saint Laurent?

By Ella Blake — Fashion Stylist | Tellar Fashion Hub — Always honest, unbiased, & unsponsored

Saint Laurent sizes small — often one to two full sizes smaller than your usual UK size — and if this is your first time shopping the brand, knowing that upfront will save you a genuinely painful amount of time in a fitting room. I say this from experience. The first time I tried on a Saint Laurent blazer, I grabbed my normal size, couldn't get the shoulders on, and had a minor dressing room crisis. Sized up twice, it fit like it was made for me. Lesson learned, never forgotten.

Saint Laurent uses French and European sizing across its ready-to-wear, so you're working with an EU scale that typically runs smaller and narrower than UK high street sizing. The brand's aesthetic — sharp, lean, Parisian — is reflected in every single cut. These are not forgiving, relaxed shapes. They are structured, precise, and body-skimming. That's exactly what makes them so stunning when they fit right, and so frustrating when they don't.

Saint Laurent Size Guide: EU to UK Conversion

Use this as your starting point, but read the garment-specific notes below before ordering — proportions vary quite a bit depending on the piece.

Saint Laurent (EU/FR)UK SizeUS SizeBust (cm)Waist (cm)Hips (cm)346280628736848466913810688709540128927499421410967810344161210082107

Ella's tip: If you're between sizes, always size up at Saint Laurent — especially in blazers and tailored trousers. Their cuts leave very little room for movement, and the difference between a 38 and a 40 can be everything.

How Saint Laurent Fits: Garment by Garment

The sizing experience varies quite significantly depending on what you're buying, so let's break it down properly.

Blazers & Jackets: These are the trickiest. Saint Laurent tailoring is cut very narrow through the shoulders and chest. If you're broader across the back or have a fuller bust, go up at least one — ideally two — sizes. The sleeves run long, which actually suits many women, but the shoulder line is uncompromising. Get this right and you'll look extraordinary. Get it wrong and you'll feel like you're wearing someone else's clothes.
Trousers: Saint Laurent trousers tend to be slim and low-rise. If you carry any volume around the hips or thighs, I'd suggest sizing up and having the waist nipped in by a tailor — it's absolutely worth it. The leg cut is long and lean, and these trousers are designed for a very specific silhouette.
Dresses: Mini and midi dresses at Saint Laurent can be slightly more accommodating than the tailoring, particularly if they're cut in a more draped fabric. That said, the jersey and silk pieces still run close to the body. Use your bust measurement as your guide if you're between sizes.
Knitwear: Knits at Saint Laurent are often more generous than the woven pieces, though still slim-cut. If you like a fitted knit, your true EU size will likely work. If you prefer a little ease, go one up.
Shoes: Saint Laurent shoes tend to run true to size or very slightly small. If you're a half size, most women find sizing up works best. Their block-heel ankle boots and stiletto pumps are iconic — and they do run narrow, so wide-fit shoppers should be aware.

Why Does Saint Laurent Run So Small?

It's not just the French sizing system — it's a deliberate design philosophy. Anthony Vaccarello, the brand's creative director since 2016, designs for a very particular silhouette: tall, lean, androgynous with a rock-and-roll edge. Think Kate Moss in the late nineties, or Charlotte Gainsbourg on a Parisian evening. The cuts reflect that vision entirely. There's a reason Saint Laurent's pieces look so impossibly cool in editorial shoots — they're cut to a very specific, unforgiving template. Knowing that going in means you can still find your perfect fit; you just need to approach sizing practically rather than emotionally.

Shopping Saint Laurent: My Honest Advice

If you can, try before you buy. The Selfridges and Harrods concessions are your best bet in the UK, or visit the Bond Street or Sloane Street boutiques. If you're ordering online, check the brand's specific size guide measurements for each piece — they do vary — and if the returns policy allows, order two sizes. The difference between a piece that fits and one that doesn't at Saint Laurent prices is significant, and the investment is worth protecting.

I've seen women size up two full UK sizes at Saint Laurent and walk out looking like a million dollars. Don't be precious about the number on the label. Nobody else is reading it.

Alternatives at Every Budget: Get That Saint Laurent Look

Saint Laurent's aesthetic — sharp suiting, sleek leather, minimal Parisian glamour — is one of the most sought-after in fashion. Here's where to find similar energy at various price points.

🛍 HIGH STREET PICKS

All Saints — Probably the closest high street match to YSL's rock-noir energy. Their leather trousers, tailored blazers, and sleek knitwear carry that same moody coolness. Sizing here runs more generously, which is a relief.
Cos — For the minimalist, architectural side of Saint Laurent. Cos does considered simplicity beautifully and at a fraction of the price. Sizing is consistent and more true to UK sizing.
Massimo Dutti — Excellent tailoring, proper fabrics, and very much in that sleek, restrained European tradition. Their blazers and straight-leg trousers are genuinely impressive for the price point.
Whistles — A quietly brilliant British brand for understated suiting and sharp separates. Their women's tailoring has real quality and an elegant, unfussy cut.
Reiss — If you want smart tailoring with a contemporary edge and you're not ready to spend designer, Reiss is almost always the answer. Their blazers in particular punch well above their price point.
Jigsaw — Understated, quality-focused, and with a grown-up sensibility that sits in a very similar lane to the quieter, more wearable end of Saint Laurent's RTW.
Me&Em — A reliable British label for women who want polish without ostentation. Their tailored pieces and silk blouses echo a pared-back Saint Laurent sensibility and tend to fit generously and well.
Mango — For the directional, fashion-forward shopper who wants a YSL-adjacent blazer or midi skirt at an accessible price. Mango's trend response is genuinely quick, and their suiting in particular has improved enormously.

✨ PREMIUM PICKS

Claudie Pierlot — A French contemporary brand with exactly the kind of polished, Parisian-leaning aesthetic that complements the Saint Laurent world. Quality is excellent and sizing is generally more forgiving than YSL.
Ted Baker — For occasion suiting and sharp dresses with a premium feel at a mid-market price. Very wearable and easy to size in — more so than most French labels.
Calvin Klein — CK's minimalist, body-conscious approach to fashion shares clear DNA with Saint Laurent's cleaner RTW pieces. Their dresses and tailored separates are worth exploring if you want that cool, unfussy American-minimalist take.

💎 INDEPENDENT & NICHE PICKS

Musier Paris — A wonderful French independent label that flies under the radar in the UK but has a genuine YSL-adjacent spirit. Their co-ords, blazers, and mini dresses are beautifully made, fashion-forward, and sized in a way that's slightly more generous than the big luxury houses.
ROTATE Birger Christensen — The Danish label beloved by fashion editors for its effortlessly cool, slightly oversized suiting and slinky occasion pieces. Their pieces have that same confident, directional energy as Saint Laurent but with a slightly more wearable, contemporary fit.

Never Guess Your Size Again — Try Tellar

If Saint Laurent's sizing has ever tripped you up — and it trips up almost everyone — Tellar.co.uk is exactly what you need. Tellar is the UK's leading clothing sizing tool, matching your exact measurements to over 1,500 brands instantly. No more guessing, no more returns, no more dressing room disasters.

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There's also the Tellar Fashion Hub — a free library of honest, unsponsored style guides from our team of stylists. No brand deals. No hidden agendas. Just useful, real fashion advice.

Visit Tellar.co.uk Try the Size Lookup Tool