What is sizing like at Saint Laurent menswear?

Saint Laurent (still YSL to most of us) runs small and is cut lean, so as a rule you should size up. If you're a true UK 40 chest in the high street, you'll almost always want the equivalent of a 42 in a Saint Laurent jacket, and the denim and knitwear are slimmer again. It's not a house that flatters a relaxed fit — the whole look is built on a narrow, sharp line.

The Saint Laurent cut, explained

Modern Saint Laurent menswear was shaped by Hedi Slimane and carried on by Anthony Vaccarello, and that skinny, rock-and-roll silhouette is baked into every measurement. The shoulders sit close, the chest is trim and the sleeves and hem are cut short and narrow. It's designed to look lean rather than comfortable, which is exactly why so many men get caught out ordering their "usual" size.

Saint Laurent uses European numbering — 46, 48, 50, 52, 54 — which maps roughly to a UK 36, 38, 40, 42, 44 chest. My honest advice: treat the number on the label as a starting point, not a promise, and try the size up alongside it wherever you can.

Tailoring and shirts

Jackets are the tightest thing in the range. They're short in the body, close through the shoulder and slim in the sleeve, so if you carry any width across the back you'll feel it immediately. Shirts are tapered through the waist and cut for a lean torso. Go true-to-size only if you're slim and want that deliberately fitted look — everyone else should size up one.

Denim

This is the piece people know Saint Laurent for, and the skinny and slim-straight jeans run genuinely small. I'd size up on the waist, and be realistic about the leg: these are not a relaxed jean and never will be. The rise is low and the line is deliberately narrow.

Knitwear and tees

Fine-gauge knits and the famous slim tees are cut close to the body. They're beautiful, but they're not forgiving — if you like a bit of room, this is another place to go up a size.

Boots and shoes

The boots are the exception to the "size up" rule. Saint Laurent footwear, and the Wyatt boot in particular, tends to run slightly long, so a lot of men take a half size down. Always try before you commit if you possibly can.

A quick confession from the fitting room: the first Saint Laurent blazer I ever pulled on I ordered in my normal 40. I couldn't get the button done up and genuinely thought I'd put on weight over Christmas. The 42 fitted like it was made for me. Lesson learned — with this house, trust the cut, not your ego.

If YSL isn't your budget — where to get the look

You don't need a Saint Laurent price tag to build that clean, lean silhouette. Here's where I'd send clients across every budget, and why.

High street

• Reiss — the closest thing on the high street to that sharp, slim tailoring. Their suits, overshirts and knitwear echo the Saint Laurent line beautifully, and the fit runs true-to-slim so it's an easy one to order.

• COS — minimalist Scandinavian cuts with excellent lean trousers and fine knitwear. Worth noting their fit has relaxed a touch in recent seasons, so check the measurements rather than assuming your usual size.

Independent and boutique

• Officine Générale — a Paris label with that same effortless French tailoring DNA. Relaxed-slim, gorgeous fabrics, and a smarter fit than most high-street options.

• Sunspel — the elevated white tee and fine knits Saint Laurent is famous for, done exceptionally well and made to last. If you only upgrade one thing, make it the tee.

• Drake's — for shirting and softer tailoring. A slightly roomier, Ivy-leaning cut if you love the quality but want to escape the skinny fit entirely.

Designer and luxury

• Celine Homme — the spiritual sibling. Hedi Slimane, who defined modern Saint Laurent menswear, now heads it, so you get the same lean, skinny silhouette and the same small sizing. Size up here too.

• Amiri — LA rock-luxe, all skinny denim and statement pieces. This is the Saint Laurent attitude turned up to eleven if that's the wardrobe you're chasing.

Stop guessing your size — Tellar does the maths for you

Saint Laurent's European numbering and slim cut are exactly the kind of thing that leads to returns. Tellar is the UK's leading free sizing tool, matching your body to more than 1,500 brands instantly so you never have to squint at a size guide again.

• Measure once using your chest, waist and hip — or just your existing size in a brand you already own.

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• Shop with confidence — no guesswork, fewer returns, better-fitting purchases.

• Always free, no downloads, works straight in your browser.

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