Tweet Facebook Mail Aussies are being urged to have a clear-out for op shops - but not to donate fast fashion pieces and only give clothes they'd like to buy themselves. Research says $20 billion dollars worth of clothes that could be donated to charity shops are sitting idle in Aussie wardrobes, with 84 per cent of people admitting to having clothes they never wear. The study by Uber and Red Cross Australia revealed more than 70 per cent of Australians hold onto clothing for years after it has gone unworn for at least a year.

LIVE UPDATES: Iran fires barrage of missiles into Israel Aussies are being urged to have a clear-out for op shops - but not to donate fast fashion. (Supplied) That's despite more than half of Aussie saying donating clothes is their preferred way of helping charities. The research found another disparity between Australians' donation and shopping behaviours.

Nearly two-thirds of respondents confessed to donating damaged clothing, while almost no one said they'd buy that. Aussies also said they're hunting for bargains on pricey items such as designer coats or unique clothing at op shops. READ MORE: Diddy accused of sexually abusing a nine-year-old boy The study by Uber and Red Cross Australia revealed more than 70 per cent of Australians hold onto clothing for years after it has gone unworn for at least a year.

(Supplied) But less than 20 per cent admit to giving these kinds of items, with synthetic 'fast-fashion' clothing being the most common donatio.