Proposals to double the size of a school could come into effect from next summer.
Essex County Council (ECC) wants to increase intake at Chipping Hill Primary School, in Owers Road, Witham, to 420 pupils.
The phased expansion would see the number of pupils admitted each year increase from 30 to 60 children, starting in September 2015.
ECC has lodged a formal notice outlining the plans following the conclusion of a public consultation period.
It is estimated that there will be a shortage of primary school places in Witham from the 2014/15 school year onwards.
Councillor Ray Gooding, ECC cabinet member for education, said: “As in many areas of the country, pupil numbers are predicted to rise in Witham and we have been working with local Witham schools to commission solutions that address the need for further places."