Two education trusts are consulting on a merger that would see them jointly running 20 schools.
If approved,more than 11,000 pupils at schools in Bristol, South Gloucestershire and Somerset would be taught under the new organisation.
Castle School Education Trust (CSET) and The Priory Learning Trust (TPLT) said they wanted to improve education "by sharing expertise".
They also said a merger would mean more resources for all schools.
In a letter to parents, trustees also promised extra training and development for staff via a teaching college.
"This investment in professional development will be a central feature of a larger organisation that could not be realised within the resources of the existing trusts," the letter said.
Called Pathway Trust, the proposed organisation would be responsible for 11,633 pupils.
Castle School Education Trust was formed in 2013 and has four secondary and four primary schools in Bristol, Thornbury and surrounding villages in South Gloucestershire. A ninth school is set to join the Trust later this year.
