What is Sizing Like at Lululemon?

TELLAR FASHION HUB — SIZING GUIDE

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

Lululemon runs small — often one to two sizes smaller than a standard UK high street fit — and their sizing system uses a US numeric scale (0 to 20) rather than UK sizing, which catches a lot of people out the first time they shop there.

I'll be straight with you: Lululemon was the brand that made me realise I'd been ordering the wrong size in activewear for years. I ordered a pair of Align leggings in what I thought was my size based on the conversion chart and they arrived looking like a second skin on a very bad day. Ordered up two sizes. They were perfect. That's the Lululemon learning curve right there, and once you've navigated it, you genuinely won't look back — the quality is exceptional. But you absolutely need to know your measurements before you spend that kind of money.

How Lululemon's Sizing Actually Works

Lululemon uses US numeric sizing: 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20. These do not correspond to UK sizes — they sit roughly two sizes below. So a UK 10 is typically a Lululemon size 6, a UK 12 is roughly a Lululemon 8, and so on. They also use XS–XXL for some items, which adds another layer of confusion.

The other critical thing to know is that Lululemon's sizing is not consistent across their entire range. Their leggings, sports bras, and tight-fitting pieces run noticeably small and compressive by design — that's intentional, the fabric is meant to hold and sculpt. Their more relaxed pieces (hoodies, joggers, oversized tees) are cut much more generously and often run true to UK size or even large.

Ella's tip: Always measure your hips for Lululemon leggings specifically — that's the measurement that matters most for fit. Their waistbands are high and firm, but if the hip measurement is off, nothing else will feel right.

Lululemon Size Conversion Table

Use this as your starting guide. Always cross-reference with Lululemon's own measurement chart on their product pages, as fit can vary by style.

UK SIZELULULEMON SIZELULULEMON (LETTER)US SIZEBUST (CM)WAIST (CM)HIPS (CM)62XXS279–8161–6386–8884XS483–8565–6790–92106S687–8969–7194–96128M891–9373–7598–1001410L1095–9977–81102–1061612XL12100–10482–86107–1111814XXL14105–10987–91112–1162016XXL16110–11492–96117–121

Sizing by Product Category

Leggings — The Align, Wunder Train & Fast and Free

Lululemon's leggings are what they built their reputation on, and the fit varies more than you'd expect even within their own range. The Align leggings — their softest, most loved style — feel almost weightless but run particularly small. Most people, myself included, find they need to size up at least one from their usual UK equivalent. The Wunder Train is firmer and more compressive; again, size up. The Fast and Free is slightly more forgiving with its mesh panels.

Align leggings: size up one to two sizes from your UK equivalent
Wunder Train: size up one — these are designed to be firm and sculpting
Fast and Free: closer to true-to-UK-equivalent, but still check your hip measurement
If you're between sizes, always go up — you want a smooth fit, not a squeeze

Sports Bras

This is where I'd urge the most caution. Lululemon sports bras are not sized like regular bras — they don't use band and cup sizing for most styles. Instead they use XS–XL or the numeric scale, based on your band measurement. If you're larger-busted (a D cup or above), many of their standard bras won't offer enough support, and the sizing won't account for cup volume at all. Their Enlite range is the exception — it's specifically designed for higher-impact support and has more structure. I'd always recommend sizing up one in Lululemon bras and going in store to try if at all possible.

Most bras: XS–XL based on band measurement only, not cup size
D+ cups: look specifically at the Enlite bra range or size up significantly
Racerback styles run tighter across the shoulders — broader-shouldered women should size up

Jackets, Hoodies & Relaxed Fits

Here's where Lululemon actually surprises people in the other direction. Their Define Jacket — one of their most popular pieces — is cut quite slim and structured; stick to the same size-up rule. But their hoodies, Scuba oversized zip-ups, and joggers? These are designed to be roomy and comfortable. I'd say go true to your UK equivalent here, or even consider sizing down if you prefer a neater fit. The Scuba hoodie in particular runs genuinely large — I'm a UK 10 and a size 4 fits me perfectly in that style.

Define Jacket: size up one from UK equivalent — it's a fitted silhouette
Scuba hoodie & oversized styles: true to UK equivalent, or size down for a closer fit
Joggers: true to UK size; waistband is adjustable so a little more forgiving

Shopping Lululemon Online vs In Store

Lululemon's website has a genuinely good size guide with a measurement tool — use it every single time, for every product, because the fit really does shift between styles. They offer free returns in the UK, which makes ordering two sizes a very reasonable approach if you're unsure. If you're near a store, the staff are well trained and refreshingly honest about sizing — they'd much rather you leave with the right size than return something.

Worth knowing: Lululemon's "We Made Too Much" section online carries discounted styles at surprisingly good prices — but once you know your size in a specific style, not before. Don't experiment on discounted pieces you can't return.

Where to Shop Instead — Alternatives to Lululemon

There's no question Lululemon makes some of the best performance-led activewear on the market. But at £88–£128 for leggings, it's not always realistic as an everyday purchase. Here are the brands worth knowing about across every price point, picked for their quality, fit consistency, and genuine customer reviews — not just because they're familiar names.

High Street Activewear Alternatives

Sweaty Betty — The UK's closest equivalent to Lululemon. Their Power leggings are genuinely excellent and run true to UK size, which makes life considerably easier. Strong size range and consistent quality.
Gymshark — Hugely popular for a reason. Their Vital seamless leggings and training shorts are well-reviewed and run true to size with a slightly more generous cut than Lululemon. Great for curvier figures.
H&M — Their Move activewear range is a genuine surprise. Good compression, decent longevity, and sizing that's refreshingly consistent. A brilliant option for everyday gym wear at a fraction of the price.
M&S — Reliable, unglamorous, and excellent. Their activewear range is consistently well-reviewed for comfort and durability. Sizing runs true to UK and they cover a wider size range than most premium activewear brands.
Abercrombie & Fitch — Their YPB (Your Personal Best) activewear line has quietly become one of the best on the high street. Excellent quality, good size inclusivity, and true-to-size fit.
Calvin Klein — Their Performance range hits that sweet spot between stylish and functional. Particularly strong for sports bras and fitted leggings. Runs true to UK size.
ASOS — The 4505 range is their own-label activewear offering and it punches above its price point. Wide size range, good variety of styles, and sizing is consistent across the collection.
Superdry — Better than its reputation suggests for activewear. Their Sport range offers solid compression leggings and training tops with a true-to-UK sizing that makes online ordering less of a gamble.

Premium Alternatives

Varley — A British activewear brand that's quietly become a cult favourite. Beautifully designed, premium fabric, and a fit that's slightly more generous than Lululemon through the hips. Sizing runs true to UK. Worn by pretty much every fitness-conscious woman in west London right now.
Alo Yoga — The American brand that gives Lululemon a serious run for its money on quality and design. Available in the UK online; sizing uses US numeric scale similar to Lululemon, so apply the same size-up rule.

Luxury & Designer Activewear

Stella McCartney × Adidas — The premium collaboration that made luxury activewear a serious category. Beautifully made, sustainable, and sized in standard UK/EU sizing. A genuine treat if you want gym wear that doubles as a style statement.
LNDR — A London-founded luxury performance brand beloved by editors and athletes alike. Technical fabrics, minimal aesthetic, and a true-to-UK sizing with a slightly more relaxed cut than Lululemon. Exceptional quality.

Two Independent Picks You Should Know

Adanola — A London-based independent activewear brand that's having a serious moment. Their Ultimate leggings are everywhere on Instagram for good reason — they're flattering, well-made, and considerably cheaper than Lululemon. Sizing is true to UK and they cover XS–XL. Worth every penny.
Girlfriend Collective — A US brand shipping to the UK that makes activewear from recycled plastic bottles. Genuinely impressive quality, an excellent size range (XXS–6XL), and a true-to-UK sizing system that makes them one of the most accessible and size-inclusive activewear brands available. A brilliant choice if sustainability matters to you.

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