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A guide to writing dates, days and time.

Days and months are spelt out in full unless appearing in T&Cs, disclaimers, contact details or mobile apps.


Dates should appear as <Day>, <Date><Month><Year>


Don’t use ‘st’, ‘nd’, ‘rd’, ‘th’ on dates.


No apostrophes on decades – it’s plural, not possessive.


For date/day/time ranges, use an em dash with no space on either side.


For times, use the 12-hour clock and use full stops to separate hours and minutes.


If you need to specify the time zone, use the following format:


Use 24/7 – not ‘24 hours, 7 days a week’.


When writing for mobile apps, the guidance for dates and times are as follows:

If a date can be qualified as today, yesterday or tomorrow, write:

If a date cannot be qualified as today, yesterday or tomorrow, write:

To write a date date with time:


Numbers 0 to 9 are generally written as words while numbers 10+ are generally written as numerals.


Use numerals instead of words for:

  • business days
  • age
  • school years
  • dates and business days
  • street addresses
  • tips articles
  • instructions
  • snappy copy
  • mobile apps where space is limited.

Avoid starting a headline or sentence with a numeral unless it’s dollar amounts, percentages, points or tips/reasons/steps, etc.