The Bourton Meadow Education Trust has expanded to take over two schools in Northampton.
Previously a Buckingham-only trust of three primary schools, it has now announced that both Spring Lane Primary, in Spring Boroughs, and Lumbertubs Primary School joined on September 1.
BMET now has five primary schools and a teacher training school.
A spokesman for the trust said the move brings greater economies of scale, sharing good practice, shared training and shared roles.
Martyn Kitson, executive head for BMET, said: “We see this as a major step in the development of the trust and we are already looking at new ways of our five schools working together. As the schoolsbecome fully integrated into our trust, we expect to see benefits to all our staff and children.”
"We are excited about the opportunities this expansion will present and regard it as an important step in ensuring that Bourton Meadow Education Trust continues to provide the best education for all its children."
Government recommendations state that local Multi Academy Trust’s with about 3,000 pupils would be the optimum size.
After taking on Spring Lane and Lumbertubs, BMET will have about 1,700 children at its school and said it will work towards 3,000 slowly.
Spring Lane Primary School had a full Ofsted inspection in 2014 and was rated 'requires improvement' but improved to 'good' in 2016.
Lumbertubs Primary School was rated 'requires improvement' in both 2016 and in April this year.
They will join Bourton Meadow Academy, Lace Hill Academy and George Grenville Academy in their new trust.
Bourton Meadow was last inspected in 2013, when it was rated 'outstanding' and George Grenville was rated 'good' in January this year. Lace Hill has yet to be inspected by Ofsted.