Jessica Portelli was trying on bikinis in her local branch of Matalan when a woman in the changing rooms told her that 'girls like her' shouldn't wear such an item.
However, instead of having her confidence knocked, Jessica took to Facebook to share an empowering message about why she'd be wearing the two piece anyway.
Uploading a picture of herself in the bikini in question, she wrote, 'I don't usually post such pictures of myself on Facebook however what happened today should be shared to raise some awareness.'
'The girl at the store today said that "girls like me" shouldn't wear a bikini ! Well girl let me tell you something , im happy with myself and my biiiigggg tummy with tiger stripes but you could have said the same thing to the girl who finally got out there and had the courage to wear a bikini and you just killed her confidence with one stupid comment.'
'You can be any size and look good ! Confidence is what makes you sexy and not just being a size 6!'
'Thank you for fat shaming me, thanks to you I got an awesome discount on my bikini. Much love #Fat ,#confident, girl!'
Since she shared it on 7th April, Jessica's post has been shared 1,750 times.
The 24-year-old, who wears a size 18-20, later explained, 'When the woman said it to me I just responded straight away telling her 'girls like her shouldn't be telling girls like me what they can wear'.
'I'd just held up the bikini so I could have a look at it before I tried it on when she said it - she was laughing at me too.'
'I told her that I'd prove her wrong so confronted her when I had the bikini on - I told her I was happy in my own body and that I love the way I look. She had nothing to say to me really and I felt so powerful going back to my changing room so I took a picture, I wasn't going to let her kill my confidence.'
She added that the store's response was kind, but she wasn't going to let the woman's comments bring her down either way.
'The man in there who offered the discount [reducing the bikini from £14 to £10] was so nice to do so but I wasn't bothered by what the woman had said, it just went straight over my head.'
'The post has been shared so many times now it's amazing I never thought it'd go this big.'