| Full date | 31 December 1999 |
|---|---|
| All-numeric date | 31/12/99 31/12/1999 1999-12-31 |
| Time | 23:59 11:59 p.m. |
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 time can be written using either the 24-hour clock (23:59) or the 12-hour clock (11:59 p.m.).