Date and time notation in the United Kingdom records the date using the day–month–year format (31 December 1999, 31/12/99 or 31/12/1999). The ISO 8601 format (1999-12-31) is increasingly used for all-numeric dates. The time can be written using either the 24-hour clock (23:59) or the 12-hour clock (11:59 pm).
