Schools Minister Nick Gibb said admissions rules must be changed so children born between April 1 and August 31 cannot be forced to go straight into year one if they wait to start school until they turn five.
He has written an open letter to encourage schools and local authorities to take immediate action, in advance of the proposed changes, and allow summer-born children to start in reception aged five if that is what parents want.
The government said summer-born children should have the “same opportunity to excel at school as their peers - even if that means starting reception a year later.”
Children usually start school in the September after they turn four but parents of summer-born children can ask to delay entry to reception for a year.
However the Department for Education said schools and councils often say summer-born pupils must go straight into year one and miss out on the reception year if they have delayed starting by a year.
In his letter, Mr Gibb said that the existing system is not working - with parents and the authorities “often failing to agree on what is in the child’s best interests”.
He said: “Parents know their children best and we want to make sure summer-born children can start reception at the age of five, if their parents think it is in their best interests.
“We are going to make changes to admission rules - but we want councils and academies to take immediate action.”
In his letter, the minister wrote: “We have decided that it is necessary to amend the school admissions code further to ensure that summer-born children can be admitted to the reception class at the age of five if it is in line with their parents’ wishes, and to ensure that those children are able to remain with that cohort as they progress through school, including through to secondary school.
“We will conduct a full public consultation in due course; and subject to Parliamentary approval will introduce these further changes to ensure that no child is forced to start school before they are ready.”