Dates in running text should always be given in their full form
For the short form, do not use leading zeros and write out the year in full.
If the day of the week is included, there is no comma after the day.
The most common way to write the date in British English is to write the day first, followed by the month and then the year (without commas):
EXAMPLE: 1 July 2014
AVOID: 1 July, 2014
AVOID: 1st of July 2014
AVOID: July 1, 2014
If the year in question is absolutely clear from the context, the year number may be left out:
When referring to decades write the decade without an apostrophe
EXAMPLE: 1990s
AVOID: 1990's
AVOID: the nineties
The letters AD come before the year number, whereas BC follows it:
EXAMPLE: AD 2000
EXAMPLE: 347 BC
CE (Common Era), BCE (Before Common Era) and BP (Before Present) also follow the year number:
EXAMPLE: 347 BCE
EXAMPLE: 333 CE
EXAMPLE: 77 BP
Use a closed-up hyphen for year ranges:
EXAMPLE: 1939-1945, 2015-2021
Note that 2015/2016 = one year: marketing year, financial year, academic year.
EXAMPLE: from 2015 to 2016
AVOID: from 2015-2016
EXAMPLE: between 2015 and 2020
AVOID: between 2015-2020
EXAMPLE: 1 May 2018 to 30 April 2019
AVOID: 1 May 2018-30 April 2019
The following formulations may be used to set the start of a period:
EXAMPLE: with effect from 1 January 2018
EXAMPLE: shall take effect on 1 January 2018
EXAMPLE: shall have effect on 1 January 2018
EXAMPLE: shall enter into force on 1 January 2018
The following formulations may be used to set the end of a period:
EXAMPLE: until 31 December 2017
EXAMPLE: until the entry into force of the Act, or 31 January 2017, whichever is the earlier
EXAMPLE: shall expire on 31 December 2017
EXAMPLE: shall cease to apply on 31 December 2017
EXAMPLE: shall apply until 31 December 2017
EXAMPLE: not later than 31 December 2017
EXAMPLE: by 31 December at the latest (This formulation should not be used for the end of the period of validity of acts because it would render that date imprecise)
NOTE: the distinction between the use of ‘by’ and ‘until’ when setting time limits and periods:
EXAMPLE: The report must be completed by 1 January 2018
EXAMPLE: The reference period of the report runs until 31 December 2017
AVOID: The report must be completed until 1 January 2018
Dates as qualifiers. In general, dates and time spans precede the expression they qualify:
EXAMPLE: the 2015-2019 work programme
AVOID: the work programme 2015-2019
EXAMPLE: the 2016/2017 financial year
AVOID: the financial year 2016/2017
EXAMPLE: the 2018 action plan
AVOID: the action plan 2018
Use the 24-hour system with a colon (or 12-hour system with a full stop, adding a.m. and p.m.):
Avoid leading zeros:
The full hour is written with zero minutes:
When using the 12-hour system, leave out .00 for the whole hour and write:
If you want to indicate whether an announced time is at standard time (autumn-winter-spring) or daylight saving time (spring-summer-autumn), use the following abbreviations for the Central European Time zone:
If the time refers to a different time zone, check the appropriate abbreviation for that time zone here.
In running texts, combine dates and times with "at":
In calendars and lists of events, combine dates and times with a comma:
Language Boutique 'Writing Numbers – Periods or Commas?' Retrieved from https://language-boutique.com/lost-in-translation-full-reader/writing-numbers-points-or-commas.html
University of Oxford Style Guide. Retrieved from https://www.ox.ac.uk/sites/files/oxford/media_wysiwyg/University%20of%20Oxford%20Style%20Guide.pdf