This partnership started as a modest cause-related marketing campaign, trading on the link between swimwear and water, but it has grown over the past decade to become a significant fundraiser.
It began in 2002, when, after a WaterAid proposal, H&M began selling a range of bikinis and donating 10 per cent of the proceeds to the charity. About £10,000 was raised in the first year, with the figure rising to £30,000 in 2004.
The partnership moved up a gear in 2006, when Kylie Minogue became the face of the product line and the bikinis were sold in more H&M stores. It developed further in 2011, when a variety of water-themed products, including dresses, blankets and sunglasses, became part of the annual promotion and a 25 per cent donation rate was introduced. This year, Beyonce is fronting the summer campaign.
"Twenty-five per cent is a very big proportion and doesn't look stingy to the customer," says Bronwen Reinhardt, senior corporate partnership manager at WaterAid. "I've worked in the third sector for 20 years and only one other company I've worked with has given 25 per cent."
The partnership has raised £500,000 in each of the past three years and £2.8m since its conception. The money raised is spent on WaterAid projects in Bangladesh, India and Pakistan, locations where some of H&M's clothing is produced.
Since 2011, H&M has made additional donations twice a year to the charity of between £40,000 and £50,000. This money was previously used to send 'goodie bags' to journalists, who now get a certificate of thanks instead.