In text, spell out the names of the days and months in full, and use the sequence day–month–year:
Wednesday 28 January 2013 [no commas] or 28 January 2013 or January 2013
not
28.1.13 or 28/1/13 or 28 Jan. 2013 or January 28, 2013
The sequence year–month–day is used in some countries, including the United States, so spelling out the month rather than using a numeric value (eg 5 for May) is important to avoid ambiguity.
Abbreviated forms may be used in tables and graphs; use the first 3 letters and no full stop:
Mon Tue Wed Thu Fri Sat Sun
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Year spans are expressed as:
- a range of years using an en dash (not a slash); truncate the second year to 2 digits unless spanning a century
1998–99 1985–95 2005–08
1995–2005 1885–1901
not
1998/99
1990s from the 1980s to the 1990s
not
1990’s [do not use an apostrophe]
mid-1990s late 1990s mid to late 1990s
Apostrophes are not needed in plural expressions of time:
3 months time 2 years time
but are required in the singular:
