Save the Children is to ban telephone cold-calling and will not share supporters’ details with other agencies in a bid to spare them from being "aggressively targeted".
The charity is expected to unveil a "supporter promise" with its latest annual report on Wednesday, which it says will also enable people to choose easily and clearly how they are contacted by the charity.
The charity is expected to say that the measure will ensure supporters have "greater control over how they give to the charity and are not aggressively targeted".
It is also expected to say that it will exercise greater oversight, including training and regulation, of any call agency it uses.
Justin Forsyth, chief executive of Save the Children, said in a statement: "Our passionate and dedicated supporters are the beating heart of our organisation and we recognise that the way we work with them has to improve.
"We have to get the right balance between raising much-needed money and making sure members of the public, who want to help us save lives and give every child the chance to learn, feel respected and valued."
The announcement follows calls for an "Olive’s law" to protect vulnerable and elderly people from cold calls from charities after the death of the 92-year-old poppy seller Olive Cooke. in May