How to Find Your Size in Banana Republic

By Ella Blake – fashion stylist | Tellar Fashion Hub – Always honest, unbiased, & unsponsored

Banana Republic runs true to US sizing, which typically comes up one size larger than UK standard — so if you're a UK 10, you'll usually be a US 4 or 6 depending on the garment. But there's more nuance to it than a simple conversion, and getting it wrong on their suiting or knitwear is an expensive mistake. Here's the full breakdown.

The Brand, in Brief

Banana Republic occupies a very specific and, in my view, rather underappreciated spot in the market. It's not fast fashion — the fabrics are genuinely considered, the tailoring is structured, and the aesthetic is that classic American smart-casual that's been quietly influencing European wardrobes for decades. Think clean-cut blazers, perfectly weighted trousers, Italian-inspired knitwear, and the kind of shirt that looks equally good tucked into work trousers or half-tucked with jeans on a Sunday.

I'll be honest — I went through a phase of dismissing Banana Republic as a bit safe. And then I bought a cashmere-blend rollneck in a sale about four years ago and have never looked back. It's washed beautifully, hasn't pilled, and still gets worn on rotation. The brand rewards loyalty. You just need to know how it fits — and that's where a lot of UK shoppers come unstuck.

US to UK Size Conversion

Banana Republic uses US sizing across its womenswear range. As a general rule, US sizes run approximately one to two sizes larger than their UK equivalents. Here's a quick reference table:

Banana Republic (US)UK SizeEU SizeBust (inches)Waist (inches)XXS / 0043231–32"23–24"XS / 063433–34"25–26"S / 2–48–1036–3835–36"27–28"M / 6–810–1238–4037–38.5"29–30.5"L / 10–1214–1642–4439.5–41"31.5–33"XL / 14184642–44"34–36"

Always cross-reference with Banana Republic's own garment measurements rather than relying solely on the size label — the brand sells across multiple categories that cut quite differently from one another.

How Different Categories Fit

This is really where the detail matters. Banana Republic isn't a one-size-fits-all proposition — the fit varies meaningfully across categories:

Tailoring and suiting: Their blazers and structured trousers are cut for a slim, contemporary silhouette. If you're broader in the shoulders or carry more volume through the hip, sizing up one and having it slightly taken in is genuinely worth considering. The construction quality justifies the cost of a small alteration.
Knitwear: This is where Banana Republic really shines — and it runs true to size or very slightly generous. I'd always stick to your usual size here unless you actively want an oversized look.
Dresses: These tend to be fitted through the body with some ease — if you're longer in the torso, bear in mind the waist seam may sit slightly high. Their Petite and Tall ranges are a genuine help here.
Denim: BR denim runs close to true size but has a very specific fit philosophy — structured and flattering rather than ultra-skinny or overly relaxed. Their high-waisted styles tend to be particularly well-cut for hourglass figures.
Shirts and blouses: If you have a fuller bust, be aware these can pull across the chest at your standard size. Sizing up and tucking in is often the more polished solution.

Stylist tip: Banana Republic regularly updates its fit system. The current "Modern" fit in their suiting range is genuinely slimmer than it was five years ago — if you last bought from them a while back, don't assume your old size still applies. Always check the current measurements on the product page.

Petite, Tall and Plus Sizing

One of the things I genuinely appreciate about Banana Republic is that they actually bother with fit diversity in a meaningful way. Their Petite range (for heights under 5'4") adjusts proportions properly — not just hems, but sleeve lengths, rise heights, and jacket body lengths. Their Tall range works similarly well. And their plus-size offering (sizes 1X–3X) maintains the same quality and aesthetic rather than feeling like an afterthought, which, sadly, still can't be said for every brand at this price point.

Similar Brands — and How They Compare on Sizing

If you love the Banana Republic aesthetic — that elevated, polished-but-relaxed American sensibility — these are the brands I'd point you towards, both for direct alternatives and for filling the gaps in your wardrobe:

Massimo Dutti — The closest European equivalent in terms of quality and aesthetic. Beautifully made, excellent fabrics, very similar price point. Note that Spanish sizing tends to run slightly small — UK shoppers often size up.
Reiss — For elevated occasionwear and tailoring with a British edge. Runs true to UK sizing and is consistently well-reviewed for fit accuracy.
Whistles — Brilliant for relaxed, contemporary workwear. Cuts generously and is very reliable for UK sizing. A great bridge between high street and designer.
Ted Baker — More overtly polished and occasion-forward than Banana Republic, but shares that commitment to considered tailoring. Runs true to UK sizing.
Hobbs — A go-to for classic British tailoring with excellent fit diversity. Particularly good for blazers and structured dresses. True to UK size.
Jigsaw — Thoughtful, unfussy dressing with excellent fabric quality. Runs true to UK sizing and their knitwear is exceptional value.
Tommy Hilfiger — For a more casual, preppy take on the same American smart-casual territory. US sizing applies, similar conversion to Banana Republic.
Crew Clothing — Relaxed, quality-focused British brand that shares the same easy, timeless aesthetic. Very consistent on sizing and brilliant for weekend pieces.

For two independent alternatives: Nili Lotan is a New York-based designer whose clean, elevated basics sit in exactly the same wardrobe territory as Banana Republic's best pieces — if you've not discovered her yet, it's worth a look. And closer to home, Coat by Kathryn Coltman is a small British brand making beautifully proportioned coats and tailoring with real attention to fit across different body shapes — genuinely impressive craftsmanship at an accessible price.

Stop Guessing — Get Your Exact Size Instantly with Tellar

If you've ever ordered a size 8 in one brand, a 10 in another, and an XS in a third and wondered why on earth sizing is so inconsistent — you're not imagining it. It genuinely is. And that's exactly the problem Tellar was built to solve.

Tellar is the UK's leading free clothing sizing tool. Enter your measurements once and instantly get your precise size across 1,500+ brands — including Banana Republic, Massimo Dutti, Reiss, COS, Arket, Everlane, and hundreds more. No downloads, no subscriptions, no faff.

Measure once — bust, waist, and hip is all you need.
Use the Store Size Lookup tool to find your exact size in any brand, instantly.
Always free, works directly in-browser from any device.

And when you've nailed your size, head to the Tellar Fashion Hub — a library of free, honest, unsponsored style guides from our team of stylists. No ads, no brand deals, just useful advice.

The Bottom Line on Banana Republic Sizing

Banana Republic is one of those brands that genuinely rewards knowing how it works. Once you understand the US-to-UK conversion and the way different categories cut, you'll shop it with real confidence — and at their sale prices especially, it's hard to beat for quality. The key takeaways:

US sizing — typically one size up from your UK equivalent, so a UK 10 is usually a US 6.
Tailoring runs slim and contemporary — size up if broader in the shoulder or hip.
Knitwear runs true to size and is excellent quality — stick to your usual.
Use their Petite, Tall, and Plus ranges if relevant — they're genuinely well-executed.
When in doubt, measure up and cross-reference with the garment measurements on the product page — or use Tellar's Store Size Lookup to cut straight to your correct size.

Once you've got your BR size dialled in, it becomes one of the most reliable wardrobe investments you can make. And that, frankly, is exactly what you want from a brand at this price point.