Dates and times

Writing about dates and times

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.

Note (for your information):  in American usage: 

Most common way to write the date in British English

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

Avoiding redundancy

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

Systems of chronology

The letters AD come before the year number, whereas BC follows it:



CE (Common Era), BCE (Before Common Era) and BP (Before Present) also follow the year number:




Time spans

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.

More examples (date spans) 

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

Start dates

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

End dates

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

Time limits

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 (or 12-hour system with a.m. and p.m.):

Avoid leading zeros:

The full hour is written with zero minutes:

When using the 12-hour system, write:

standard time and daylight saving time

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.

combining date and time

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