A report to Lancashire County Council's Cabinet at its meeting on Thursday, August 8th recommends approving a permanent expansion of 30 places each year from September 2020 at both Shuttleworth and Unity colleges.
Both campuses will be expanded to allow for the extra pupils, subject to relevant planning permissions being obtained.
Extra places needed for September this year have been provided temporarily by the schools.
The colleges will then expand permanently from September 2020 through the provision of additional permanent accommodation on the existing sites.
The proposed expansion would increase the number of places for new applicants at Shuttleworth College, in Burnley Road, from 210 to 240 each year from 2020. The expansion will create an extra 150 places at the school within five years.
The number of places at Unity College would increase from 240 to 270 each year. The expansion will also create an extra 150 places at the school within five years.
Edwina Grant OBE, Lancashire County Council's executive director for education and children's services, said: "One of our key responsibilities at the county council is making sure that there are enough school places to meet demand.
"The two colleges are already providing the extra places that are needed on a temporary basis, and cabinet will consider the recommendation to make this permanent."