Shelter Cymru and Crisis criticise homeless donations via councils
Money collected by councils to give to homeless people may not be reaching those who need it most, charities claim.
'Diverted giving' campaigns run by a number of Welsh authorities encourage the public to donate rather than give money directly to those on the streets.
Shelter Cymru and Crisis said they were hard for people in need to access.
Neath Port Talbot council, the latest to launch a scheme, said it aimed to meet homeless people's long-term needs.
Cardiff council has been running its 'Give DIFFerently' scheme since March, allowing people to make contactless payments towards organisations working with homeless people.
Swansea council's 'Have a Heart - Give Smart' was launched in January, and other areas such as Newport have campaigns up and running or in development.
To access the funds, homeless people must make an application to the scheme explaining what they need the money for, according to the charities.
John Puzey, director of Shelter Cymru, said: "Street homelessness and begging are not easy issues to solve and councils will have the best of intentions when they choose to support such schemes - but we are concerned about the possible negative impacts.
"The money spent on these schemes could be put to better use to address some of the barriers that are preventing people from accessing assistance.
"We should be concentrating our efforts on providing permanent homes, together with the support necessary to make it work."
Karen Grunhut, director of Crisis' south Wales service, added: "Not all homeless people beg and not all people begging are homeless and some of the language and imagery used in the schemes is very unhelpful to public understanding.
"We're speaking out against the schemes but we will continue to work alongside the organisations involved."
A spokesman for the Welsh Local Government Association, which represents councils, said making options available for people to help homeless people across Wales was something it would support.
Sian Morris, community safety manager at Neath Port Talbot council, said its scheme, also called 'Have a Heart, Give Smart', is in addition to outreach work employed by the local authority.
"One of the main reasons the street-vulnerable do not engage [with the system] is failing to remember/ keep appointments or because they are worried about filling in forms." she said.
"I think we have to accept that there are always going to be people who will not accept help, just as there are those who choose to be homeless as a lifestyle choice. This doesn't mean we stop trying to help.
"If you give money to a beggar on the street that may meet their needs for one day; we are hoping the funds from the scheme will help meet their needs for the rest of their life."