WaterAid is calling on licensees to ask customers to give a pound every time they spend a penny.
The charity, which provides clean water and sanitation to the world's poorest communities, is looking for help from pubs to mark World Toilet Day.
The event takes place on November 19 and pubs are being asked to collect cash from customers using their facilities.
Chris Stewart, freeholder at Brighton pub the Prince Albert, is among the licensees who will be taking part.
He said: "We already support the Tap into WaterAid initiative and this is another way of helping out.
"It might be a bit much to charge customers every time they go but we will certainly ask people when they come in off the street just to use the toilets."
Money raised from the collections will go to helping the 2.6 billion people in the world who do not currently have safe sanitation.
The charity is also calling on the UK government to increase international aid so that sanitation and water are brought to an extra 100 million people by 2015.
WaterAid's Susie Henderson said: "The pub sector has already shown great support to WaterAid through various fundraising initiatives this year.
"Getting customers to donate a pound when they spend a penny is another way that will help people throughout the world.
"Having access to water and sanitation is something that we can often take for granted but in the developing world diarrhoeal diseases caused by poor sanitation and unclean water kill 4,000 children every day."
To find out more or to make a donation visit www.wateraid.org/publicanappeal
Tap into WaterAid
This year The Publican has teamed up with WaterAid to promote the Tap into WaterAid initiative. Laws introduced by the last government mean pubs now have to provide free tap water when asked. We are urging pubs to ask customers for a 15p donation of at least for every free glass of water provided. Through Tap into WaterAid and other fundraising activities including our recent pub quiz and proceeds from our Proud of Pubs Summer Ale we have raised more than £15,000.
For more information visit Tap into WaterAid