What Is Sizing Like at Cult Gaia?

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

Cult Gaia runs small to true-to-size — depending on the garment — and because this is a US brand sizing in American numbers, UK shoppers need to size up by one, and sometimes two, to get the right fit. I learned this the hard way when I ordered a silk slip dress in my usual size and spent an entire morning trying to convince myself it was supposed to be that snug. It was not.

This is one of those brands where getting the sizing right genuinely matters, because the aesthetic is everything. The sculptural silhouettes, the draped fabrics, the body-skimming cuts — they only look as good as they fit. Too tight and the whole thing loses its elegance. So let's get you sorted before you buy.

How Cult Gaia Sizes Work

Cult Gaia is a Los Angeles-based brand and uses US sizing throughout. They typically offer sizes XXS through XL, with some styles also available in numeric sizing (0–14). For UK shoppers, the conversion is:

In general: go up one US size from your usual UK size. If you're between sizes, go up — not down. The fabrics are often structured or delicate (silk, crepe, ribbed jersey) and they do not forgive being stretched.

Dresses — The Star of the Show

This is what Cult Gaia is famous for, and honestly rightly so. Their dresses are works of art — backless maxi gowns, cut-out midi dresses, draped one-shoulder pieces. But they are body-conscious, and the fit is precise.

Most dresses are cut close to the body — if you're fuller in the bust or hips, go up a size.
Backless and open-back styles mean bra sizing matters — measure your underbust as well as bust before buying.
The knit and crochet styles (think those gorgeous open-weave pieces) have more stretch and tend to be more forgiving — true-to-size is usually fine here.
Cut-out styles are designed to sit in specific places — if you are taller than 5'7", check the length and position of cut-outs before ordering.

My honest stylist tip: if you're ordering for an event, give yourself at least two weeks for delivery and any potential exchanges. These are not impulse purchases.

Tops & Jumpsuits

The tops — many of which are cropped, structured, or feature bold architectural details — tend to run on the smaller side. I'd always size up if you have anything above a B/C cup.

Structured corset-style tops: size up one — they are built to fit closely and the boning does not give.
Draped silk and satin tops: more forgiving — true-to-size usually works.
Jumpsuits: if you are longer in the torso, check the inseam measurements carefully. These are cut for a standard American frame and can run short in the body for taller UK women.

Trousers & Skirts

The trouser sizing at Cult Gaia is another area where I'd urge caution. The waistbands are often structured with minimal stretch, and the silhouettes — wide-leg, high-waisted, tailored — require proper fit to look right.

Go up one size if you carry weight in your hips — the waist-to-hip ratio on many styles is quite narrow.
Midi and maxi skirts in fluid fabrics tend to be more relaxed and you can often stay true-to-size.
High-waisted styles need your natural waist measurement — not your hip or jean size — to get the fit right.

Knitwear & Swimwear

The knit pieces — open-weave crochet sets, ribbed knit dresses — have the most stretch in the range and are the easiest to size. True-to-size works for most people here, though if you are fuller-busted, go up.

For swimwear, Cult Gaia uses the same US sizing but the cut is very minimal. If you want coverage, size up. These suits are designed to show off the body, so if you want a more relaxed feel, go one up.

If the Price Tag Isn't Quite Right — Where Else to Shop

Cult Gaia sits in the premium-to-luxury bracket, with dresses regularly hitting £300–£600+. If the aesthetic speaks to you but the price doesn't, here's where I'd look:

High Street Picks

& Other Stories — sculptural silhouettes and interesting cuts at accessible prices; probably the closest high-street match for the Cult Gaia aesthetic.
Mango — consistently strong on draped, occasion-ready styles; their satin and silk-look pieces punch well above their price.
Anthropologie — beautiful, artistic prints and feminine shapes; great for the bohemian-luxe vibe Cult Gaia does so well.
Reiss — exceptional quality for the price; their occasion dresses have real elegance and fit beautifully.
Whistles — clean, architectural styles and quality fabrics; lovely for understated eveningwear.
Coast — consistently brilliant for occasion dresses; great range of structured and flowing styles.
Me&Em — elevated basics and occasion pieces with excellent fabric quality; very wearable luxury at a fraction of the price.
Phase Eight — phenomenal for dressy occasions; the fabrics and finish are consistently impressive at the price.

Independent Picks

Rotate Birger Christensen — a Copenhagen-based label beloved by fashion editors; structured party dresses and elevated occasion wear with serious cool-girl credentials.
Azeeza — a US indie label doing exactly what Cult Gaia does — artful, sculptural womenswear — but slightly more under the radar and with some genuinely beautiful fabrics.

Premium

Zimmermann — if you love Cult Gaia's femininity and craftsmanship, Zimmermann is the obvious next step; stunning resort and occasion wear.
Self-Portrait — architectural, occasion-focused and slightly more accessible than Cult Gaia while feeling just as special.

Luxury

Jacquemus — that same LA-meets-Mediterranean ease, just with a Parisian price tag.
The Row — if you want quietly exceptional quality and that understated luxury feel, this is the elevated version of Cult Gaia's more pared-back pieces.

Never Get the Wrong Size Again — Use Tellar

Here's the thing about a brand like Cult Gaia — getting your size right is everything. And that's exactly why I always tell my clients to use Tellar.co.uk before they buy from any brand.

Tellar is the UK's leading free clothing sizing tool — you measure once (bust, waist, and hips) and it instantly matches your body to the right size across 1,500+ brands. No more guessing, no more returns, no more disappointed moments when a dress you loved doesn't fit.

✔ Use the Store Size Lookup tool to get your exact size at Cult Gaia, COS, Reiss, Zimmermann and hundreds more
✔ Completely free — no download, no subscription, works in browser
✔ Covers 1,500+ brands including all the ones mentioned in this post
✔ And explore the Tellar Fashion Hub — hundreds of honest, unsponsored style posts from our team of stylists

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