Numbers, dates and time

Writing numbers

Use numerals instead of words

Using numerals for numbers makes content easier to read, especially if the number is above 9.

In certain circumstances, spelling the number out will make more sense than using numerals.

If using ordinal numbers, like first and second, spell those out up to ninth. After that, use 10th, 11th and so on.

Use commas for numbers over 999

Use a comma for numbers above 999.

Plural numbers do not need apostrophes.

Spell out millions and billions

If you're not writing about money, spell out millions and billions.

If you're writing about money, abbreviate millions and billions.

Be consistent when writing about money

Don’t use a space between the currency symbol and the number.

When a user is checking out, include a decimal point and the pence even if the amount is a round number.

In normal sentences, don’t include a decimal point or the pence if the amount is a round number.

Write out the entire number for all amounts under £1 million.

Split phone numbers into 3 segments

For geographic landline numbers, separate the area code from the local numbers with a space, and then separate the local numbers into two segments.

Depending on the location, the area code could be 3, 4, or 5 digits. For example, 020 for London, 0161 for Manchester, or 01792 for Swansea.

For mobile numbers, split them into three segments with 5 digits at the start and two segments of three at the end.

Writing dates

Consider the circumstances

There's not one ideal date format for every situation. You should find the one that works best for the circumstance.

We've included some guidance around the most preferred formats and when and how to use them.

Use the long date format

Where possible, write dates as 2 March or 27 October 2020. Don’t include ‘th’ or any commas.

Only include the year if it’s relevant for the user. Include the day if that information is likely to be useful. If you do, the year can be left out of the date, especially if it's the current year.

Avoid numerical dates

Where possible, don't use numerical-only date formats as they can be confusing. If space is an issue, you can use a 3-letter abbreviation for the months. Don’t use a full stop after the month.

If you need to use a numerical date, use the format DD/MM/YYYY.

Use the word 'to' for date ranges

For date ranges, use ‘to’ instead of a hyphen as it’s easier for screen reader users to understand. If your date range is in the same month, still include the month both times.

Writing time

Use the 12-hour clock

Use the 12-hour clock where possible, followed by ‘am’ or ‘pm’ without any spaces.

Use the word 'to' for time ranges

For time ranges, use ‘to’ instead of a hyphen as it’s easier for screen readers to understand. If your time ranges are both in the morning or afternoon, still include am/pm after both times.

Be careful writing about midnight

Use ‘11.59pm’ instead of ‘midnight’. Midnight is the first minute of the day, not the last.

Use ‘midday’ instead of ‘12pm’ or ‘noon’.

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