What Is Sizing Like at Hackett?

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

Hackett runs slim and on the small side, thanks to its European sizing roots — so if you're shopping it, expect it to come up tighter than your usual UK high street size, and size up if you're between two. That's the short answer. The longer answer is that Hackett is one of those names I get asked about constantly, usually by women buying for a partner — and then quietly eyeing up the blazers for themselves. So let me unpack exactly how it fits, who it's actually for, and where to look if you love the heritage-British look but want it cut for you.

First, the Honest Bit: Hackett Is a Menswear House

I'm not going to pretend otherwise — Hackett London, founded in 1979 on Portobello Road, built its name on quintessentially British menswear. Sharp tailoring, rugby shirts, Aston Martin Racing collabs, the lot. There isn't a sprawling womenswear line to size up here. But I'm including it for two very good reasons.

The borrowed-from-the-boys blazer is having a real moment. An oversized Hackett wool blazer thrown over a slip dress is one of my favourite styling tricks, and I've sent more than one client into the menswear section on purpose.
The fit logic is genuinely useful — if you understand how a European-rooted brand sizes its tailoring, you understand how to shop the whole heritage-preppy category.

So this is a fit guide with a styling twist. Stay with me.

My Own Hackett Sizing Fail

A few winters ago I bought a Hackett quilted gilet to wear oversized over chunky knits — that effortless countryside-pub look I'm forever chasing. I went up to what I thought was a generous size, assuming menswear would swamp me. Reader, it did not. Across the chest and arms it was snug to the point of being structured, not slouchy. I'd completely forgotten that Hackett's outerwear runs tighter through the shoulders and chest than the relaxed silhouette I'd pictured. Lesson learned: with this brand, the fit name on the label matters more than the size number.

How Hackett Actually Fits

Here's what I've pieced together from styling clients, scouring reviews, and a fair few personal trial runs:

It's cut slim and European. Garments routinely come up smaller than equivalent UK high street sizing. Trousers in particular follow EU sizing, so a "32" isn't always the 32 you expect.
Jackets and gilets run tightest across the arms and chest — these are the pieces to size up on, especially if you want that intentional oversized drape.
Knitwear is true to size on its own, but go roomier if you plan to layer it over a shirt.
Casual staples — tees, hoodies, polos — get the most "true to size" feedback from buyers, so trust your usual here.
Read the fit name first. Hackett labels its cuts as Classic (relaxed, roomier), Slim (tapered, body-following) and Contemporary (the middle ground). Shirts come in Slim and Classic. The fit name tells you far more than the number ever will.

Approximate Size Conversion

UK Women'sMenswear (chest)EUBust (cm)8XS / 34"4482–8510S / 36"4686–8912M / 38–40"48–5090–9414L / 40–42"50–5295–9916XL / 44"54100–104

These are approximate — Hackett varies by line, season and country of manufacture, so always treat them as a starting point rather than gospel. If you're buying menswear to wear oversized, work from your bust measurement and then go up a size for that deliberate slouch.

Where to Shop for the Hackett Look — Cut for Women

If it's the heritage-British, polished-preppy aesthetic you're after — crisp shirts, neat tailoring, country-meets-city polish — these are the brands I'd send you to instead, all with proper womenswear ranges.

High Street & Mid-Market

GANT — the closest preppy cousin going, with brilliant women's oxford shirts and rugby stripes. Runs true to size.
Tommy Hilfiger — Americana-preppy with sharp blazers and chinos; the women's tailoring is excellent value.
Polo Ralph Lauren — heritage done properly. Slightly generous fit, so consider sizing down on the shirts.
Crew Clothing — the British nautical-preppy answer, and reliably true to UK sizing.
Jack Wills — collegiate British staples for a softer, younger take on the look.
Charles Tyrwhitt — for the perfect women's tailored shirt; their non-iron cotton is a wardrobe workhorse.
Hawes & Curtis — proper Jermyn Street shirting and blazers, sized for women.
Hobbs — quintessentially British smart tailoring and structured coats; true to size with a flattering cut.

Premium

Reiss — elevated tailoring with that same crisp, considered finish. Runs slim, so don't be afraid to size up.
Massimo Dutti — quietly luxurious wool blazers and trousers at a fraction of designer prices.

Luxury & Designer

Ralph Lauren Collection — the full heritage fantasy, beautifully made.
Loro Piana — the gold standard for understated, fabric-led luxury tailoring.

Two Independent Finds I Love

Holland Cooper — a British equestrian-heritage label that nails exactly the Hackett mood, but designed entirely for women. Tailored blazers, velvet, and that polished country-to-city versatility.
Fairfax & Favor — independent British heritage at its best, brilliant for the boots, suede and tweed pieces that complete this whole look.

My Verdict

Hackett is a slim-cut, European-sized menswear brand — wonderful for borrowing that oversized blazer or gilet, but always size up on the tailoring and read the fit name before the number. And if you want the heritage-British polish cut properly for you, the brands above will get you there without a trip to the menswear floor. Whatever you're eyeing up, measure yourself once, shop from your numbers, and you'll save yourself the returns faff every single time.

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