Does FS Collection Run True to Size? A Stylist's Honest Sizing Guide

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

FS Collection runs small — particularly in its dresses and formalwear. If you're shopping the brand for the first time, especially for an occasion, sizing up is almost always the right call. I've seen this catch people out more times than I'd like to admit, and I've been there myself: I ordered a midi dress in my usual size 12 for a friend's birthday dinner and spent the evening tugging it down. Lesson learned. Sizing up to a 14 the following season? A completely different — and much more comfortable — story.

About FS Collection

FS Collection is a London-based womenswear brand founded in 2010, best known for its occasionwear, party dresses, and seasonal wardrobe staples. You'll find it stocked on ASOS, Amazon and its own website, and it's become a go-to for weddings, evenings out, and anything that needs a bit of polish without a designer price tag. Think floaty midis, fitted wrap dresses, knitwear and dressy jumpsuits — all at high street prices.

The range covers UK sizes 6 to 18, with a decent spread of occasion-forward silhouettes and on-trend colourways each season. It's genuinely a lovely brand. But the sizing? It requires a little know-how.

So, Does FS Collection Run Big or Small?

FS Collection runs small, especially across its dresses and more structured pieces. The brand uses standard UK sizing on the label, but the actual garment measurements tend to come up narrower than what you'd expect from high street equivalents. Here's what I've noticed across the range:

Formal and occasion dresses: These are the worst offenders. Fitted bodices, zip-up backs and no-stretch fabrics mean there's very little forgiveness. If you're anywhere between sizes, always go up.
Wrap and midi styles: More comfortable, but still cut on the slimmer side — particularly around the bust and shoulders.
Knitwear and casual tops: These tend to be closer to true size, and softer fabrics give a bit more wiggle room.
Jumpsuits and playsuits: Fit depends hugely on the cut. Wide-leg styles with elasticated waists are more forgiving; tailored ones — size up.
Maxi and midi lengths: Cut for a height of roughly 5'4"–5'6". If you're petite, expect to need a hem. If you're taller, check the length description carefully.

Who Does FS Collection Sizing Suit Best?

The brand's designs are cut with a slim to hourglass figure in mind. Narrower shoulders and a defined waist work brilliantly here. If you have a fuller bust, broader shoulders or wider hips, I'd strongly recommend sizing up one — possibly two if you're ordering a structured formal gown for something important like a wedding or graduation.

The side-zip closures that appear across a lot of the occasionwear range are particularly unforgiving. There's no stretch to help you ease in; you're working with a fixed measurement. It's the kind of thing that's totally fine once you know your FS Collection size — but it can be a nasty surprise if you're shopping blind.

💡 Quick verdict: Size up one from your usual high street size for dresses and formalwear. True to size or size up for knitwear and casualwear. Petites, check length measurements before ordering.

How FS Collection Compares to Other Brands

To give you a reference point — FS Collection dresses fit tighter than high street brands like Monsoon (which cuts generously and is a brilliant occasionwear alternative with beautiful embellished options), Phase Eight (consistently well-cut dresses with a reliable fit guide and a favourite for weddings and smart occasions), and Coast (occasion-focused and tends to run true to size across its dress range).

If you're used to shopping at Ted Baker — which also runs small — FS Collection will feel familiar. Reiss and LK Bennett are also slightly generous compared to FS Collection, so if you're a 12 in either of those, a 14 in FS Collection wouldn't surprise me at all.

For casual and everyday pieces, the sizing gap narrows a little and you'll find it sits more in line with brands like Whistles, Hobbs and Me&Em, all of which have a clean, considered fit and solid sizing consistency.

My High Street & Independent Alternatives to FS Collection

Love the aesthetic but want something with a more predictable fit? Here are some of my picks — all chosen for their similar occasionwear and everyday dress offering:

Phase Eight — One of the best British brands for occasion dresses. Reliable sizing, beautiful fabrications and the kind of cuts that actually flatter a range of body shapes. A go-to for wedding guest dressing.
Coast — Occasion-led and consistently well-sized, with a good range of midis, maxi gowns and cocktail dresses. Tends to run true to size and is great for events.
Monsoon — Generously cut, brilliant for a curvier frame, and stunning embellished options for weddings and celebrations. Runs bigger than FS Collection.
Ted Baker — A similar aesthetic to FS Collection with a slightly more premium feel. Also runs small, so bear that in mind, but the quality is a step up.
Reiss — Clean, polished occasionwear and everyday dresses. Sizing is more consistent and generous than FS Collection.
LK Bennett — A brilliant British brand for smart-casual and occasion dressing. Midi dresses and wrap styles are consistently well-cut and flattering.
Whistles — More understated than FS Collection but excellent quality for everyday dresses and smart separates. True to size.
Hobbs — Sophisticated British occasionwear with great sizing consistency. Particularly strong for wedding guest and smart occasion outfits.

And my two independent picks for this post:

Ghost London — A beloved British brand with a cult following for its fluid, bias-cut dresses and feminine silhouettes. Beautiful for occasions and easier to size than FS Collection. ghostlondon.com
Finery London — An independent British womenswear label known for its considered prints, elegant dresses and relaxed occasionwear. Sizing is true to label and the aesthetic is genuinely lovely. finerylondon.com

Stop Guessing Your Size in FS Collection — Use Tellar

The whole reason I started talking about Tellar is because sizing in brands like FS Collection is genuinely confusing — and getting it wrong before an event is stressful. Tellar.co.uk is the UK's leading free sizing tool, matching your actual measurements to the right size across 1,500+ brands instantly.

📏 Measure once — bust, waist and hips — or just enter your size in a brand you already know
🔍 Use the Store Size Lookup tool to get your exact FS Collection size — and your size in 1,500+ other brands
✅ Completely free, no downloads, no subscriptions, works straight in your browser

The Tellar Fashion Hub is also packed with free, honest, unbiased style guides from our team of stylists — no ads, no sponsored posts, no agenda. Just genuinely useful fashion content.

Find My FS Collection Size →

Or visit tellar.co.uk to explore the full Fashion Hub.

More from the Tellar Fashion Hub: