Information is not currently collected on vacancies in schools. Information on numbers of pupils on roll and planned admission numbers in schools can be combined to estimate how many unfilled places exist in free schools.
In October 2015 there were (a) 2,088 unfilled places (13%) in mainstream free schools in London, (b) 189 unfilled places (7%) in mainstream free schools in Yorkshire and the Humber, and (c) 7,674 unfilled places (15%) in mainstream free schools in England. 79% of mainstream free schools that opened since 2012 had one or more unfilled places which is the same proportion as for all mainstream state funded schools at May 2015.
These figures are based on pupils in reception to year 11 in mainstream free schools and will include schools which had only recently opened.
 Figures are based on (a) total number of pupils on roll across years Reception to year 11 from October 2015 and (b) total planned admission numbers across these year groups. It excludes year groups which are not yet populated. Figures exclude 16-19, Special and AP free schools. Some free schools build up their capacity in year groups gradually, so for example they may open with one class of 30 in Reception in year 1, and in year 2 expand to have two classes of 30 in Reception. This means that the current capacity in a free school in Reception, for example, may not be the eventual capacity once the school is at full capacity.
 See School capacity: academic year 2014 to 2015 at https://www.gov.uk/government/publications/school-capacity-academic-year-2014-to-2015