The two charities will join forces from 15 November to create one charity to support parents and families and those who work with them. Parenting UK’s name and services will be retained within the wider Family Lives brand. The new structure will allow for the continuation of current work.
Six of Parenting UK's seven staff will transfer across as part of the merger. The remaining staff member's contract ends before November.
Family Lives will retain all existing 80 members of staff.
Jeremy Todd, chief executive of Family Lives, said: "Working together will allow a greater provision of services to members and the families we serve, alongside providing a stronger voice to influence policymakers and government."
Pamela Park, chief executive of Parenting UK, will become business development director and oversee membership services, sector projects and broader business development projects. She said: "We are very pleased to be joining with such a strong charity with the same aim of supporting families and parenting.
"This will ensure a continued focus on developing and enhancing the parenting workforce and ensure we maintain a voice for the sector in the long term so that families continue to receive the high-quality and professional support they need and want."
Family Lives changed its name last year from Parentline Plus.