Designer fashion fit guide: Finding your size in L'Agence, Marella & Patrizia Pepe
One of the biggest mistakes women make when buying designer fashion is assuming that a size 10 in one brand is a size 10 everywhere. It's not. European designer brands size differently than British high-street retailers, and worse, they size differently from each other.
L'Agence tends to run small. Marella runs true to size but with room in the shoulders. Patrizia Pepe runs generous. None of this is a secret—it's just information that doesn't get communicated clearly anywhere. So you end up with expensive returns or, worse, a wardrobe full of pieces that don't fit right.
This guide is built from years of customer experience at No19 Boutique. Use it to order with confidence.
L'Agence: The golden rule is always size up
L'Agence runs small. Not slightly small—noticeably small. This is partly by design (L'Agence values a close, precise fit), but mostly it's because they use Italian production and Italian sizing conventions.
If you're a UK size 8–10, order a size 2 US (which is roughly UK 10–12). If you're a UK 10–12, order a size 4 US. If you're a UK 12–14, order a size 6 US.
L'Agence blouses are the most critical to size correctly because they're tailored pieces. A too-small blouse doesn't stretch—it pulls at the buttons and the shoulder seams sit too far back. Too-large looks sloppy. Aim for the blouse to skim your body with about one inch of give across the bust.
L'Agence dresses can handle a wider fit because they're often made from fluid fabrics. Still, size up from your usual size—the brand's silhouettes are designed to work with a bit of extra room.
L'Agence jeans are the exception. They run small AND they have minimal stretch (they're often 100% cotton). Go up two sizes from your usual. If you normally wear a 28, go for a 30 in L'Agence. Breaking in a pair takes a wear or two, but once broken in, they hold their shape beautifully.
Marella: True to size, with generous shoulders
Marella runs true to UK sizing, which makes them refreshingly straightforward. If you're a UK 10, order a UK 10. If you're a UK 12, order a UK 12.
The catch: Marella cuts generously through the shoulders. If you have narrow or sloped shoulders, Marella's shoulder seams might sit too wide, which throws off the entire silhouette. If you have broad shoulders, Marella is perfect—it's one of the few designer brands that doesn't force you to size up just to fit through the shoulders.
Marella dresses fit predictably. What you see is usually what you get. The brand is Italian, so the silhouettes are body-conscious without being tight. A size 10 dress will skim your curves without clinging.
Marella tops and jackets are where you notice the shoulder room. If you're unsure, order your true size. If the shoulders are slightly too wide, the overall proportions are usually still flattering because Marella designs for movement.
Marella trousers are a highlight—they fit beautifully through the hip and thigh, with a high waistband that's genuinely comfortable. Order your usual size.
Patrizia Pepe: Go down a size (or two for petite frames)
Patrizia Pepe runs generous. This is partly brand philosophy (they design for drape, not structure) and partly Italian sizing tradition (Italian brands tend to run larger than other Europeans).
If you're a UK 10, try a UK 8 in Patrizia Pepe. If you're a UK 12, try a UK 10. If you have a petite frame (under 5'4"), consider going down two sizes.
Patrizia Pepe dresses are the most forgiving because they're usually made from soft, fluid fabrics. The extra room creates beautiful drape instead of looking baggy. Smaller sizes actually work better in their dresses—you get the flowing silhouette without the fabric engulfing you.
Patrizia Pepe tops are trickier because structure matters. If you order a size too large, the neckline can gap, and the sleeve length can overwhelm your proportions. Stick to one size down from your true size in tops.
Patrizia Pepe trousers and skirts are worth getting right because the cuts are often quite specific (high-waisted, slim through the hip, cropped). Order one size down and check the length—some styles are cut for taller women.
Universal fit rules across all brands
Shoulder seams should sit at your actual shoulder bone, not forward and not back. If they're off by more than half an inch, the piece won't move right, no matter how good it looks on the hanger.
Armholes should be comfortable. You should be able to lift your arm without feeling like the seam is digging into your pit. European designers often cut smaller armholes than British brands, which creates elegant proportions but can feel restrictive if you go too small.
Waistbands should sit at your natural waist, not your hips. Designer trousers are usually designed with a higher rise than high-street shops. If the waistband hits your hips, you've gone up a size.
Hems matter. Many designer pieces have intentional hem lengths that are longer than what you'd expect. L'Agence dresses often hit mid-calf or below the knee. Patrizia Pepe trousers sometimes crop at the ankle in an intentional way. This is by design—don't automatically shorten without checking reference images first.
The return policy secret
If you're unsure, order multiple sizes and return what doesn't work. No19 Boutique's return policy is straightforward—unworn, untagged items within 7 days. Use this to your advantage when trying a new-to-you designer.
The first piece from each brand is often a sizing exploration. Once you own one L'Agence blouse or one Marella jacket, you'll know how that brand fits your body. Future orders become easier.
Final thought
Designer sizing isn't arbitrary—it's intentional. The fit differences between L'Agence's precision tailoring and Patrizia Pepe's fluid drape reflect actual design philosophy. You're not just buying clothes; you're buying the designer's vision of how women should move and look. Sizing correctly means you get to experience that vision as intended.
Shop our collections of L'Agence, Marella, and Patrizia Pepe knowing exactly what to expect.