A new campaign is calling for an end to "fake tan shaming" after a survey found 60% of women using the products have had unpleasant experiences after using the products.
The survey, by Censuswide on behalf of St Tropez, found Women in the North East are the most likely to wear tan for a confidence boost, with 70% giving that as a reason for using such products.
It also found 44% of women admit to judging their fellow females for wearing a sunless tan - and more than half a million women in the UK have experienced negative comments online specifically for wearing fake tan.
Of those asked, 60% of women who have experienced judging looks and insults say that their confidence was seriously knocked, with respondents saying they went straight home, and they did not wish to leave the house.
In response, St Tropez has launched a campaign - You Set the Tone - calling for an end to fake tan shaming.
A spokeswoman for the firm said the findings were "shocking".
"In an age where positive body confidence messages are high on the agenda in schools, the workplace and from consumer brands - it appears that it's women who need to start supporting the cause," she said.
"But, in spite of the stigmas, the survey revealed that 42% of UK women who proudly wear fake tan cite their two main reasons for doing so as looking well and feeling confident.
"In addition, having a post-holiday tan also features in the top three confidence boosters, which also suggests that golden glowing skin inspires us to feel our best and on top of our game.
"These insights have led St.Tropez to boldly address the stigmas surrounding self tanning head-on, with a motivational campaign entitled You Set the Tone which aims to highlight that tanning is more about how you feel than how you look and a goal of empowering women to feel more confident, every day."
Philanthropist and charity founder Katie Piper is among those backing the campaign.
The television presenter and former model said: " "I'm backing St.Tropez's You Set the Tone campaign as it's vitally important for women to feel confident in their own skin and with their own bodies, and if a beauty product or regime can help them achieve this, it can only be positive.
"Every woman has an individual reason for how they wear their make-up or hair and it's no different with self tan. Tanning doesn't just add colour, it can also help to even out skin tone, cover up pigmentation or redness, allow you to wear less make up or go without heavy foundations.
"The survey findings show that us women need to be supporting and celebrating each other and finding ways to improve our self-esteem and ultimately, our mental wellbeing."
Michaella Bolder, St.Tropez tanning expert, said: "Tanning isn't a one look fits all, for some it's a deep dark bronze but for the majority, it's a natural, healthy post-holiday glow - but most importantly, it's one that suits them. It's empowering to be able to offer women that feeling of confidence and positivity all year round."
She added: "Self tanning in itself can be a bit intimidating and if the main reason women are being judged on their tan is poor application then St.Tropez are doing everything they can to provide products which are mistake-proof - after all, it's the safest way to tan.
"Self tanning technology has come a long way from the orange tones, patchy legs, stained hands perception of the past and whether you're a novice or regular tanner, there is a product for everyone."
The Censuswide survey took place in March 2019 across the UK with a sample of 1,512 women aged 16-55.
It found those in the North West were the keenest tanners, with 48% of women using products. The region was also found to be the most judgemental, according to the survey with another 48% of women asked admitting to judging others who used fake tan.
Liverpool was the top tanning city with 55% of those asked admitting to using the product.
Those in the South East wear the least tan, according to the survey, with 73% saying they never wore it.
More than of women in Yorkshire (55%) said they wore fake tan before a holiday, compared to only a third (35%) of women in London
Women in the East of England are the least judgemental with only a third (33%) admitting to it