What Is Sizing Like at Seraphine?

Seraphine runs generous — so in the vast majority of cases you should order your normal, pre-pregnancy size and resist the urge to size up. This is the single biggest mistake I see women make with the brand, and it’s an easy one to fix.

I’ve styled more pregnant clients than I can count, and Seraphine comes up again and again because the cut is so flattering. But the brand’s sizing is famously roomy, which catches people out. Let me talk you through exactly how it fits, where it’s quirky, and which size to actually buy.

Does Seraphine come up big or small?

Big. Seraphine sits roughly one to two sizes more generous than your average high street label, and this is most noticeable in the dresses. As a rough translation, a medium at Seraphine fits much like a large at H&M. The whole point of maternity design is room to grow, so the brand builds in extra space across the bump, hips and waistband by default — you don’t need to add more yourself.

A few things worth knowing before you order:

Order your pre-pregnancy size. The over-bump panels and stretch fabrics are engineered to expand with you, so your usual size will see you through to the third trimester for most styles.
Dresses are the most generous. If you’re between sizes or carrying small, the smaller size will almost always be the right call.
They run long. Hems are cut longer at the front to sit over a growing bump, so if you’re petite (5ft4 and under), factor in a possible trip to the tailor.
Fabric quality varies. Some pieces are gorgeous and built to last; a handful feel thinner than the price suggests. Order, try, and send back what doesn’t earn its place.

My honest take from the fitting room

I’ll be straight with you — my own Seraphine win and fail happened on the same afternoon. I bought a wrap dress in my true size and it was perfect: forgiving, photographed beautifully, took a client all the way through to a 38-week wedding. The fail? I’d also panic-ordered their jeans a size up “to be safe” and they were swimming on me by week 30. Lesson learned, and now I pass it straight on: trust your normal number.

The over-bump jersey jeans and the jersey wrap dresses are where Seraphine genuinely shines. The bump bands are soft and supportive without digging in. Tailored blazers and structured occasion pieces are where I’d be most careful — try those on early, because the generous cut can read slightly boxy if you go up.

Where else to shop for bump-friendly fit

Seraphine isn’t your only option, and mixing maternity specialists with clever high street stretch pieces is how I build a budget-friendly capsule for clients. Here’s where I’d send you.

High street

ASOS — the best one-stop shop for maternity online, with a huge dedicated range and brilliant filtering by trimester and style.
H&M — the Mama line is superb value, with soft jersey basics and over-bump leggings that rival Seraphine for a fraction of the price.
Next — reliable, well-cut maternity workwear and dresses, and refreshingly true to size compared to Seraphine.
New Look — great for affordable, on-trend maternity pieces you won’t feel precious about wearing into the ground.
Gap — the maternity denim and soft tees are properly comfortable and cut for real, all-day wear.
Mango — not a dedicated maternity line, but their fluid, stretchy midi dresses are some of the best non-maternity bump options going.
Topshop — (via ASOS) still a go-to for fashion-led maternity denim and dresses with a younger edge.

Premium

Hush — not maternity-specific, but their relaxed, drapey dresses and elasticated trousers carry a bump beautifully and earn their place long after.
Whistles — for elevated wrap and tiered dresses with built-in give — ideal occasion pieces that don’t scream “maternity”.
Me&Em — cleverly engineered, forgiving silhouettes designed to flatter a changing shape; investment buys you’ll keep.

Luxury / designer

Max Mara — the fluid, beautifully draped dresses and soft tailoring accommodate a bump with quiet elegance, and the quality lasts a lifetime.

Two independents worth knowing

Tiffany Rose — a British independent specialising in occasion and bridal maternity wear. Exquisitely made, true to size, and the brand I send brides-to-be to without hesitation.
Isabella Oliver — the considered, slow-fashion answer to Seraphine. London-designed, beautifully cut wrap pieces and ruched dresses with a more tailored, less generous fit.

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The bottom line: buy your normal size at Seraphine, expect a generous and slightly long fit, and lean on the dresses and over-bump jersey rather than the structured tailoring. Do that and you’ll get the gorgeous, flattering result the brand is loved for — minus the returns faff.