What Is Sizing Like at Simply Be? A Straight-Talking Stylist's Guide

By Ella Blake — Senior Fashion Stylist & Founder | TellarAlways honest, unbiased, & unsponsored

Simply Be sizes run generously — typically a half to a full size larger than the label suggests — with a cut that's designed to flatter curves through the hip and thigh, though the fit varies quite a bit depending on the garment type.

I'll be honest: I didn't always take Simply Be seriously. For years I walked straight past it — in my head it was catalogue-land, aimed at someone much older than me. Then a client of mine, a brilliant size 18, came to a styling session in the most incredible pair of dark-wash straight-leg jeans I'd seen all season. Simply Be. I've been paying proper attention ever since.

If you're a size 14 to 32 and you've been struggling with high-street brands that seem to think "plus size" just means scaling up a size 10 without changing the proportions, Simply Be is actually worth your time. Let me walk you through what you need to know before you buy.

The Overall Size Picture

Simply Be's core range runs from a UK 10 to a UK 32, though the real sweet spot — where the most styles live — is 14 to 28. The sizing philosophy is rooted in curve-fit, which means more room through the hips and thighs and a longer back rise in trousers. For curvy and pear-shaped bodies especially, this is a genuine relief compared to brands that cut everything straight up and down.

That said, the fit isn't completely consistent across categories. Here's my honest breakdown:

Tops and blouses: Generally run true to size, though some of the relaxed styles can feel boxy across the shoulders if you're narrow up top. If you're fuller in the bust, you may want to size up one for a more comfortable fit.
Dresses: The stretch jersey styles are the most reliable — they accommodate a range of proportions beautifully. More structured shift styles can be a touch large in the waist if you're curvy rather than straight-up-and-down.
Denim: This is the trickiest category. The waist tends to run a little smaller relative to the hip measurement — which is good news if you struggle with the dreaded waistband gap, but if you're more of a straight shape, you may find the hip fit is generous. My advice: check the specific fit guide per jean style, because they vary more than most brands.
Knitwear: Runs true to size to slightly generous. The slightly relaxed cut is flattering rather than shapeless in most cases.
Occasionwear and formal: Can run quite large. I'd recommend sizing down by one if you're between sizes in their formal or structured pieces.

Fit Tips I Actually Use With Clients

A few things I tell every client who's shopping Simply Be for the first time:

Don't assume your usual size. Simply Be fits a different shape to most high-street brands, so your usual size 16 here may feel like a roomy 18 on top.
Read the reviews. Simply Be's website has really useful customer photos and reviews that specifically mention fit — use them. A review from someone with your body shape is worth ten size guides.
Their Shape Sorter feature is genuinely helpful for filtering styles by body shape — use it, especially for dresses and jeans.
If you're petite (under 5'4"), their petite range is edited but worth checking — the standard lengths can be overwhelming on a shorter frame.
The tall range (from around 5'8") is excellent for trousers and jeans — this is one of the few brands where taller plus-size women aren't an afterthought.

What Simply Be Does Really Well

Honestly? The denim is genuinely impressive. The variety of fits — wide leg, barrel, straight, skinny — and the fact that they actually cut jeans with a curve-appropriate rise and hip width means fewer clients coming back to me saying nothing fits. Their occasionwear has also improved enormously — the sequin midi dresses around party season are a client favourite, and they hold up well in terms of quality for the price point.

Activewear is a sleeper hit, too. The sports leggings have a high enough waistband to stay put, and the fabric doesn't go sheer under pressure. I know that sounds like a low bar, but for plus-size activewear it genuinely isn't.

Where to Look Elsewhere: Brand Alternatives by Budget

Simply Be is great, but it's not the only option. Depending on what you're looking for, here's where I'd point clients across the budget spectrum:

HIGH STREET PICKS

ASOS Curve — Probably the most extensive plus-size range on the high street right now, with brilliant trend-led pieces. Sizing can vary wildly by brand, so check the individual size guides carefully.
M&S — Consistently good for workwear and occasionwear in extended sizes. Their Per Una and Autograph lines in particular have improved dramatically. Runs fairly true to size.
Next — A genuinely solid performer in curvy and plus-size denim and occasionwear. I regularly send clients there for smart-casual trousers. Fit is reliable and consistent.
New Look Curves — Very good value and surprisingly trend-aware. Their wide-leg trousers have had a real moment. Tends to run true to size.
River Island Plus — One of the better-designed plus ranges on the high street in terms of silhouette. The occasionwear is particularly strong. Runs slightly small compared to other brands at the same number.
Phase Eight — Not often mentioned in the plus-size conversation, but they go up to a UK 22 and the quality is noticeably higher than most high street. Cuts are elegant, fit is sophisticated.
Monsoon — Goes up to a size 24 and the print quality is beautiful. The boho and occasion styles in extended sizes are genuinely lovely. Tends to run generous, especially in unstructured styles.
Boden — Their extended range has expanded significantly. Known for flattering, considered cuts and excellent jersey fabrication. Runs true to size, though the styling is more classic than fashion-forward.

PREMIUM OPTIONS

Sosandar — A premium brand that's brilliant for curvy figures. Beautiful fabrics, thoughtful cuts, goes up to a UK 22. Consistently strong in blouses, trousers and occasionwear. A favourite of mine for client wardrobes.
Reiss — Goes up to a UK 18 in most lines, with some styles to 20. The quality and cut are exceptional — a Reiss dress in a size 18 will often outperform anything else at twice the price.
Me&Em — Excellent quality, goes to a UK 18 across most styles. The cuts are designed to be wearable rather than purely editorial, which makes them incredibly flattering on real figures.

LUXURY & DESIGNER

Marina Rinaldi — The luxury plus-size benchmark. If you're dressing for a really important occasion and want something that feels truly exceptional, this is where to go. Italian tailoring at its finest, sizing from a UK 14 to 28.
Stella McCartney — Extended sizes to a UK 18 in many lines. The sustainable fabrication and clean tailoring make this a genuinely worthwhile investment piece for a special wardrobe staple.

INDEPENDENT & NICHE BRANDS WORTH KNOWING

Anna Scholz — A London-based designer who has been creating thoughtful, genuinely fashion-forward plus-size womenswear for over two decades. The quality is exceptional and the cuts are actually designed with a larger frame in mind — not an afterthought. Sizes UK 14–30.
Navabi — A curated online boutique specialising in premium plus-size labels from across Europe. Think beautiful fabrics, considered design, and the kind of styling that plus-size shoppers almost never get from the high street. A real find.

POWERED BY TELLAR

Stop Guessing. Find Your Exact Size in 1,500+ Brands.

Sizing varies brand to brand — sometimes dramatically. Tellar is the UK's leading sizing tool, matching your measurements to over 1,500 women's brands instantly. Measure once, shop confidently forever.

Enter your bust, waist, hips — or just your size in a brand you trust
Instantly matched to your precise size in any brand — Simply Be, ASOS, Reiss, M&S and 1,500+ more
Always free. No downloads. Works in-browser on any device
Plus: a Fashion Hub packed with free, unbiased style advice from our team of stylists

VISIT TELLARTRY THE STORE SIZE LOOKUP