The nursery, Rosedene at Kader Primary School, will provide care for 36 children.
The new setting will see the group run a total of nine nurseries, offering more than 340 places.
Just three months ago, the nursery group opened a new setting at Mowden Park Rugby Club in Darlington
Rosedene Darlington is registered to care for 55 children from six weeks to eight years old. Along with providing wrap-around care for children attending nearby schools, the setting opens some Saturdays to coincide with rugby matches.
The nurseries in Saltburn, Hemlington and Guisborough in North Yorkshire and Easterside, Ormesby and Egglesont in North East England are all rated good or outstanding.
Rosedene Nurseries director Clare McCullagh said, ‘An aspiring and loyal workforce delivering an outstanding service is key to ensuring our children are happy and enjoy their learning experiences before they start school.
‘Rosedene Nurseries strives to develop strong partnerships with neighbouring schools, working with children and parents.’