Nearly 82 per cent of women with big feet, size eight and above, are not too comfortable with their big feet, so they often lie about it.
More than three-quarters bought shoes online to avoid anyone knowing their size and nearly half (47 per cent) said they had lied to their partner and friends about how big their feet were, reports the Daily Express.
Nearly two-thirds also felt uncomfortable having to ask assistants for their size.
The study also found that women's feet are getting bigger - with an 80 per cent increase in size nine shoes.
The average female foot is now one and a half sizes bigger than 10 years ago - and experts say it is because women are taller and heavier.
Carie Barkhuizen, of Debenhams, said: "Buying shoes online can be tricky.
"We were surprised to learn that a case of cold feet was behind it," she added.