M&S vs Next: How Their UK Clothing Sizes Really Compare

Clothing sizes aren’t universal in the UK, even between two major high-street retailers like Marks & Spencer (M&S) and Next. While both brands claim to offer standard UK sizing, there are subtle but significant variations in their fit, measurement ranges, and cut across garments. If you’ve ever found that you’re a size 10 in one and a 12 in the other, you’re not imagining it.

This technical guide breaks down how M&S and Next clothing sizes differ across women’s wear, including tops, trousers, jeans, dresses, and outerwear—so you can shop more confidently without the trial-and-error.

1. General Sizing Philosophy

M&S Sizing Approach: M&S is known for its more generous cut, particularly in waist and hip areas. Their sizing historically catered to a broader demographic, including mature shoppers, and has tended to favour comfort over a slim fit.
Next Sizing Approach: Next leans more true to high-street average, with a slightly narrower fit across the bust, waist and especially the thigh. Many customers report that Next runs smaller than M&S by around half a size.

2. Bust, Waist and Hip Measurements Compared (UK Size 12)

Measurement	M&S Size 12	Next Size 12
Bust	92 cm	90 cm
Waist	76 cm	74 cm
Hips	100 cm	96–98 cm

🔍 On average, M&S adds 2–4 cm more ease around the hip and bust, meaning the same labelled size can feel noticeably looser in M&S compared to Next.

3. Dresses & Tops

M&S: Dresses often have more bust room and are cut with a looser waistline. Great for apple and rectangle body shapes or those preferring a more forgiving fit.
Next: More form-fitting in the bust and hip. Women with hourglass or pear shapes may prefer this cut, though it may feel snug in the arms and shoulders compared to M&S.

4. Trousers, Jeans & Bottoms

M&S: Roomier in the waist and upper thigh, often using comfort waistbands, especially in work trousers and linen styles.
Next: Tends to have slimmer thighs and more defined waists in tailored styles. Jeans, in particular, run tighter—especially in skinny and slim fits.

📏 Example: If you're a 30" waist, you may wear a UK 12 in M&S trousers, but need a UK 14 in Next depending on cut.

5. Petite and Tall Fit Availability

M&S: Offers both Petite and Long lengths in key lines, especially jeans, trousers, and coats. Petite cuts still tend to have generous room through the waist.
Next: One of the strongest UK high-street options for Tall, Petite, and Curve fits. Their Petite range is cut proportionally smaller throughout—not just in length—making it better suited to petite women under 5'3".

6. Plus-Size and Curve Ranges

M&S Curve: Inclusive range up to size 32 with flatteringly cut pieces and considered tailoring. Generous armholes, bust darts, and longer hems make their plus-size pieces functional and comfortable.
Next Curve: Sizes to 26. Slightly more fashion-forward but cuts tend to run narrower at bust and arms, which may not suit all plus-size figures equally well.

7. Sizing Consistency & Fabric Impact

M&S is relatively consistent across product types and fabrics, with a fit model that supports standardisation. Stretch fabrics in M&S tend to stretch more generously.
Next can vary more depending on garment cut and trend. Their sizing is slightly more fitted, so rigid fabrics (e.g., denim, cotton poplin) can feel tighter and less forgiving than the same labelled size in M&S.

8. Which Brand Runs Bigger?

In most cases, M&S runs slightly bigger than Next. Expect to size up when moving from M&S to Next, particularly in fitted garments or trousers.

That means if you’re:

A UK 12 in M&S, you may need a 14 in Next
A UK 14 in Next, you might fit a 12 or 13 in M&S

But instead of guessing, use the tool below…

Skip the Guesswork with Tellar.co.uk

Tired of guessing whether you’re a 10 in M&S and a 12 in Next? Let Tellar.co.uk do the work.

🛠 How Tellar.co.uk Works

Tellar is the UK’s Leading Sizing Tool, matching your unique body measurements to over 1,500+ brands in real time—including M&S, Next, Zara, Reiss, COS, Arket and more. No more decoding size charts.

You can:

✅ Create a free Tellar.co.uk profile
✅ Input your body measurements once (or your known size in a brand)
✅ Use the Store Size Lookup to find your exact size in any brand

Plus, get instant access to our free Fashion Hub, a growing library of thousands of posts covering every sizing question, style guide, and brand comparison you can think of.

🧵 Always honest. Always unbiased. Always free.

📚 Want More Help? Read These

🔗 Follow Tellar.co.uk

Instagram: @Tellarsizing
Twitter/X: @Tellar100
Facebook: Tellar Sizing
Pinterest: TellarUK

Final Thought

If you’ve ever found yourself asking “Why doesn’t my size stay the same across brands?”, the answer is simple: it doesn’t. But with Tellar.co.uk, it can. Ditch the confusion, ditch the size guides, and start shopping smarter. It’s free & easy.

Find your size in 1,500+ brands real-time. It’s free & easy.