http://www.legislation.gov.uk/ukdsi/2016/9780111143988/schedules
The European Union Referendum (Date of Referendum etc.) Regulations 2016
en
King's Printer of Acts of Parliament
2016-07-18
REFERENDUMS
REPRESENTATION OF THE PEOPLE
2016-01-01
These Regulations set the date of the referendum on whether the United Kingdom should remain a member of the European Union. They also prescribe the length of the referendum period, the start of the period for applications for becoming a designated organisation and periods for reporting of donations or regulated transactions. They extend to the whole of the United Kingdom and Gibraltar.
The European Union Referendum (Date of Referendum etc.) Regulations 2016