The NSPCC was founded in 1884 and protects children across the UK. It offers a wide range of services for both children and adults, including national helplines and local projects. Importantly, the NSPCC recognises that survivors of child abuse are often adults before they wish to deal with this issue and have considerable experience dealing with adults seeking support for childhood abuse.
NAPAC describes itself as the only national organisation focused on supporting adults who have been abused in any way as children. Most children who are abused don't talk about it until they become adults.
NAPAC exists to support survivors of child abuse when they want to talk and receive support.