Does vanity sizing make it impossible for YOU to shop online?

Does vanity sizing make it impossible for YOU to shop online? With retailers shut, Femail reveals how dress sizes vary as much as 2.5in between stores – and how to find your perfect fit

  • Femail has compared size 12 waist measurements across 15 popular retailers 
  • Found there is a difference of 2.5in between the neatest and most generous
  • Variations in sizing are proving problematic as shoppers are forced online 

With non-essential retailers closed, customers are relying on online shopping to keep their wardrobes stocked.

But the discrepancy in sizing between brands means many are left confused over which size they should buy.

Femail has compared the waist measurements for a size 12 across 15 brands popular with British shoppers and found there is a difference of 2.5in between the neatest and most generous.

Femail has compared the waist measurements for a size 12 across 15 brands popular with British shoppers and found there is a difference of 2.5in between the neatest and most generous. Above, a graphic illustrating the difference in waist sizes between stores

How size 12 clothes measure up 

Retailer

Cos

Monsoon 

New Look 

River Island 

Zara 

M&S 

Reiss 

Whistles 

Asos 

Topshop 

George by Asda 

H&M 

PrettyLittleThing 

Next 

Tu by Sainsbury’s  

Waist size (inches)

28.5

28.5 

29 

29 

29.1

29.5

29.5 

29.5 

30 

30 

30

30 

30.5 

30.5 

31 

 

Cos, a Swedish retailer that is part of the H&M group, comes up smallest with a 28.5in waist, while Sainsbury’s clothing brand Tu is the largest at 31in.

This wide range means shoppers might have to try several sizes to find garments that fit, which can be problematic – and expensive – when ordering online. 

‘Size discrepancy causes much frustration to shoppers,’ celebrity stylist Rochelle White told Femail. ‘Shoppers will order the same thing at twice as they are unsure of the size and fit. 

Cos, a Swedish retailer that is part of the H&M group, comes up smallest with a 28.5in waist

Sainsbury's clothing brand Tu is the largest at 31in

Cos (left), a Swedish retailer that is part of the H&M group, comes up smallest with a 28.5in waist, while Sainsbury’s clothing brand Tu (right) is the largest at 31in.

‘Not only is this a hassle for shoppers, but also costly for the brands as many offer free returns, which is a cost that they cover. 

Stylist’s tips for buying clothes online 

1. Make a note of your measurements and check them against the brand’s size guides. These aren’t always 100% but they’re a good place to start. 

2. Check on the individual item to see if there are fit recommendations. Some pieces might be smaller or larger than the ones the brand typically sells. 

3. If you are able to, buy a few pieces from the brand to get an idea of the size and fit. You will find certain brands run bigger or smaller. Some will also fit your body type better than others. 

4. Watch any videos on the product page to see how the garment moves. If a full body skirt is too heavy for the model, for example, it might not work for a woman with a petite frame.

5. Make use of the ‘what’s my size’ or interactive chat options if available 

‘If shoppers don’t feel like they are being catered for, they will turn away from brands and not engage or shop with them.’

A woman with a 30in waist, for example, would just squeeze into a size 14 from Cos (30in) but would have to opt for a size 16 (31.5in) to have a bit of wriggle room. At Sainsbury’s, the same woman would fall between a size 10 (29in) and 12 (31in).

The issue sparked a discussion on Mumsnet this week after one user accused Marks & Spencer of being the biggest offender of ‘vanity sizing’, a term used to describe sizing that is overly generous. 

The argument is that shoppers will be more likely to buy from a brand that uses ‘vanity sizing’ because she can fit into a smaller size than usual.

When it comes to shopping online, Rochelle said the best approach is to pay close attention to sizing charts. 

She said: ‘My recommendations is have a good understanding of your measurements and use a brands size guides as guidance (they aren’t always right). 

‘Buy a few pieces from their selection to get a feel for their sizes, fit and style. As each brand is different, it is good to get a good understanding of them. 

‘If the brand have videos watch them and see how they fit the model when she walks etc.

‘Some websites now have the “what’s my size” function which lets you add in your details and they recommend the “perfect fit”.’