There has been an 84 per cent increase in the number of parents asking for their summer-born children to delay their admission to Reception.
The findings have been published this morning by the Department for Education and cover a two-year period from 2015 to 2017.
Children usually start school in the September after they turn 4, but parents of children born between 1 April and 31 August, also known as "summer-born" children, can ask to delay entry to Reception for a year.
While the School Admissions Code requires school admission authorities to provide for the admission of all children in the September following their fourth birthday, a child does not reach compulsory school age until the “prescribed day” following their fifth birthday (or on their fifth birthday if it falls on a prescribed day).
The figures published today show that local authorities received 916 requests from parents to delay their child's school entry from 2015-16 to 2016-17. Of these, three quarters were granted.
A year later, 1,750 requests to delay school entry were received by the same number of local authorities - an 84 per cent increase.
The DfE document says this indicates "that parents’ awareness of their rights regarding admissions may be increasing".
However, the number of requests is still relatively low, at less than 0.5 per cent of the five-year-old population in the local authorities concerned.
Parents with higher incomes were significantly more likely to delay their summer-born child’s admission to Reception.
Almost half (47 per cent) had a household income of £50,000 or more, which is twice the median household income.
The DfE document warns that the research is based on a small sample size.
It also suggests that delaying children's admission to Reception does not have a significant impact on their attainment.
There was an increase in phonics scores of 0.87 marks for delayed entry summer-born children between 2014-15 and 2015-16, "but that is not a statistically significant improvement", says the document.
However, previous research has shown that summer-born children are twice as likely to miss early years benchmarks.
There have also been calls from parents to allow them to delay their summer-born children's entry to Year 1.
Schools minister Nick Gibb has said that the government intends to change the admission rules to prevent summer-born children going straight into Year 1 if they defer.