National Export System (NES) and New Computerised Transit System (NCTS): Overview of the National Exports System
A Customs declaration is required for all goods exported. NES is an electronic-based system that allows exporters to lodge an export entry with Customs before the goods leave the UK. The option to submit a paper declaration - C88 Single Administrative Document (SAD) is now only available for standard full pre-entry procedures at the frontier.
Detailed guidance and information on NES is contained in EXPP2000 and Notice 275: Customs export procedures