What Is Sizing Like at Oceanus?

Oceanus runs true to its UK size label across a fairly narrow XS to XL range (roughly a UK 6 to 14), but the fit is firm, body-sculpting and deliberately snug — so if you're between sizes, fuller through the bust or hip, or buying one of their heavily beaded pieces, you'll almost always want to size up. That's the short version. Now let me explain properly, because Oceanus is one of those brands where the number on the label tells you far less than the construction does.

So, how does Oceanus sizing actually run?

Oceanus is a British luxury swimwear and resortwear label, famous for its hand-embellished, crystal-encrusted, head-turning pieces. The brand uses a standard XS–XL grading, and on paper a 10 is a 10. In reality, the fabric does most of the talking. Their swimwear is double-lined and built on a powerful stretch base designed to hold you in — gorgeous and confidence-boosting, but unforgiving if you've gone too small. I always tell clients to think of Oceanus swimwear like a really good piece of shapewear: it should feel supportive, never like it's leaving a mark.

The embellishment catch (learn from my mistake)

Here's where I have to confess to a proper styling fail. A few summers ago I bought a beaded Oceanus one-piece in my "usual" size for a shoot in Mykonos, assuming the stretch would sort everything out. It didn't. The beading sits on a firmer, less giving panel, so the suit fit beautifully lying down and dug in the second I stood up — and once it was wet, the sheer weight of the crystals dragged it lower than I'd planned. Mortifying on a busy beach. The lesson stuck: the more embellishment, the less stretch. So size up on anything heavily beaded or sequinned. A plain stretch-mesh cover-up might fit you in an 8, while a corseted, crystal-covered dress will happily want a 12.

Swimwear vs dresses: two different beasts

The dresses deserve their own warning. Many Oceanus gowns and jumpsuits are built with boning or corsetry through the bodice, which means the bust is cut quite precisely and there's very little give. If you're a fuller cup, buy to your bust measurement rather than your dress size, and size up if you're in any doubt — you can always have a waist nipped in by a tailor, but you cannot add room to a boned bodice. The relaxed crochet, knit and soft-jersey pieces are the happy exception: they're far more forgiving and tend to sit close to true size.

My fit cheat sheet for Oceanus

Measure your bust, waist and hips before you buy — never trust your "usual" size on a luxury brand.
Size up for heavily embellished swimwear and any boned or corseted dresses.
Stick to your true size for crochet, knit and soft stretch cover-ups.
Fuller bust? Buy to your bust and have the rest tailored.
Beading adds real weight — a wet, embellished suit drops, so a snugger leg and strap is your friend.

Where else to shop for embellished glamour

If Oceanus is sold out in your size, or simply over budget, here's where I send clients for that same glossy, occasion-ready energy — from the high street up to designer.

High street

Monsoon — the queen of embellished occasionwear; brilliant for beaded holiday dresses at a fraction of designer prices.
Coast — sleek, structured occasion dresses with a flattering, reliably true-to-size cut.
Phase Eight — lovely detailing and generous, dependable sizing for special-occasion pieces.
River Island — trend-led, affordable glam swimwear and resort sets if you only need the look for one holiday.
Seasalt Cornwall — proper coastal swimwear with supportive, true-to-size shapes built for actual swimming.
Hush — effortless resortwear and a strong holiday edit, with a relaxed, slightly roomy fit.
Mint Velvet — elevated, relaxed-luxe resort pieces that nicely bridge high street and premium.

Premium

Hunza G — the cult crinkle-stretch label whose one-size pieces genuinely fit a UK 6–14; the ultimate antidote to sizing stress.
Melissa Odabash — jet-set British resortwear with a sophisticated, true-to-size fit and serious staying power.

Luxury / designer

Heidi Klein — the UK's go-to for polished, beautifully constructed luxury swim and resort.
Zimmermann — romantic, embellished resort and occasion pieces; size up, as the cut runs dainty.

Two to watch — my left-field favourites

Stay Wild Swim — an independent London label making recycled, sculpting swimwear with a genuinely supportive fit.
Davy J — a brilliant British indie using regenerated ocean plastic, designed to actually stay put when you swim and dive.

How Tellar takes the guesswork out

This is exactly why I built Tellar — it's the UK's leading sizing tool. You measure once (bust, waist, hip, or simply your existing size in a brand you already know) and your body is instantly matched to over 1,500 brands. Never squint at a size guide again.

Pop your measurements in once at tellar.co.uk.
Use the Store Size Lookup to get your precise size in any brand — COS, Reiss, Everlane, Arket and more.
Always free, no downloads needed — it works straight in your browser.

There's also the Tellar Fashion Hub: a library stacked with free posts from our top stylists. Honest, unbiased, independent and always free — style advice, top picks and the best brands, all in one place.

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