Writing numbers

Write all numbers 10 and over as numerals, up to 999,999.

Write numbers zero to nine as words unless they are technical or precise, such as dates, figure or table titles, or relate directly to the statistics being presented.

On the one hand…
This is the most effective of the two measures…
7 March 2017
Figure 1

Where a range crosses the 10 boundary, use numerals.

9 to 12 respondents, not nine to 12 respondents

Write out rankings first to ninth, then use numerals. Do not use superscript for “st”, “nd”, “rd” and “th”.


A sequence of numbers should use the same format for both, which should follow the higher number.

6th out of 12

Do not use abbreviations of “numbers”, such as “no” or “nos”. They can be read incorrectly.

Use commas to separate thousands in numbers of four digits or more, and never spaces (except when writing years – these should have no punctuation).


Avoid writing sets of numbers together.

In 1961 just over 2,500 births were recorded


In 1961 2,543 births were recorded

Use a 0 where there is no digit before the decimal point in a number.


Do not start a sentence with a numeral. Rearrange the sentence accordingly.

The number of people who drive a car is 52.4 million


52.4 million people drive a car

Do not use a hyphen to indicate a range of numbers, separate with “to”.

Around 15 to 20 people attended the event.

Number rounding

Rounding numbers can make them easier to read and compare, although this must be balanced against the loss of precision.

The level of rounding you use (for example, one decimal place or two significant figures) should be effective, and chosen according to the intended use. It should also be consistent throughout your piece of writing.

For more detail about intended users, go to Number rounding in the Data visualisation section.

For more information about presenting tables and graphs (including rounding on page 7), see the Government Statistical Service’s Good Practice Team guidance.

Generalised numbers

Write out generalised numbers.

hundreds of years
in their thousands
per thousand women

Millions and billions

Write out and use lower case.

2.5 million
148 billion

Do not use “0.xx million” for numbers less than 1 million, unless part of a sequence of numbers

Page numbers

Use the fewest digits possible while remaining clear. Separate them with “to”.

1 to 4
10 to 18
132 to 148

Plus and minus

In text, when referring to positive and negative numbers, write out “positive” and “negative” in

positive 7
negative 3

In a dataset, use the symbols with no space between them and the number.



Write out and hyphenate fractions.


Avoid using too many fractions as it can be difficult to compare several together.

Also avoid using large denominators.


Write out decimal fractions as numerals. Use the same number format for a sequence of fractions and decimals.

0.75 and 0.45


Use the percentage symbol with no space between it and the number.


Always write “percentage” and never %age.

Use the same number of decimal places for a sequence of decimal numbers.

6.25% and 7.60%

A percentage point is the difference between percentages. A value of 10% falling by 1 percentage point becomes 9% (10% has 10 percentage points). A fall of 1% would result in a value of 9.9%


Use the format “[Date] [Month] [Year]” (depending on what information you have) written out with no commas. If the day of the week is relevant, then put it before the date. Do not include “st”, “nd”, “rd” and “th” after the date.

12 March 2014
Monday 3 March 2014

Write out months in full. If space is limited (such as in a table) use the shortened version with no punctuation, but not for June and July. Do not use shortened versions of months in titles.

Retail sales in Great Britain: September 2017

Date spans

Use the format “[date] to [date]” to state the reference period for your data.

2009 to 2010

If using months within the same year, only write the year after the subsequent month.

July to September 2014

If the period spans years, add the relevant year after each month.

July 2013 to September 2014

For a period between two dates, use the format “between [date] and [date]”.

between 1986 and 2014
between July and September 2014
between 2001 to 2003 and 2017 to 2019

Do not use hyphens, dashes or forward slashes to indicate date spans. It is quicker to read “to”, and special characters can cause problems for screen readers.


Decades should only have an apostrophe when they are a possessive, not a contraction.

a 1960s’ child
the 1960s were great


Use ordinal numbers when referring to a particular century.

21st century


Define the quarter, the months covered, and the year. Explain which months are included in the quarter in the first instance of each section, and only include the quarter and year in every subsequent instance. Abbreviate the months to three or four characters. In titles write the months in full and avoid using quarters.

Quarter 1 (Jan to Mar) 2019
Quarter 2 (Apr to June) 2019
Quarter 3 (July to Sept) 2019
Quarter 4 (Oct to Dec) 2019
The value of goods imported narrowed in Quarter 2 (Apr to June) 2019. Within imports of goods, the largest decreases recorded in Quarter 2 2019 were…

Financial, tax and academic years

For financial years, write “financial year ending” and the abbreviation “FYE” in brackets, followed by the year for the first time you use it in each section. After that, just use the abbreviation and the year. The full phrase should be written out again for the first mention in each section.

financial year ending (FYE) 2011
FYE 2011

If a date span covers this period but you do not want to refer to the financial year, either write “year ending March 2018” or “April 2017 to March 2018” depending on what you think will meet your users’ needs.

If your data source uses another recognised date span such as the academic or tax year, write this in each instance without using hyphens, dashes or slashes.

tax year ending 2019
academic year 2020 to 2021

Include a definition of the months included in a non-calendar date span near its first reference in the text so that all users can understand the dates you are referring to. This will only need to be defined in the first instance of your bulletin or article.

Change in data over time

If you need to show a change in the data between two date spans, include the month and year in brackets after each figure. Use the format “from [amount] (month year) to [amount] (month year)”.

Northern Ireland has seen an increase of 20% in the number of acceptances, from 9,878 (April 2016 to March 2017) to 11,877 (April 2017 to March 2018).

Reference across different time periods and countries

When reporting on different geographic areas that use data from different date spans, state the month and year of the data collection after each area. Use the appropriate format for the date range, and place the information in brackets.

… the largest category of households reported to be applying for help with homelessness across the UK was single people (based on data for October to December 2018 in England; April 2017 to March 2018 in Scotland; January to December 2018 in Wales; and April to September 2018 in Northern Ireland).


Do not use the 24-hour clock. Do not insert spaces between the number and the letters, and do not use any punctuation except as shown.


Use the same number format for time spans.

8:00am to 5:30pm
1pm to 3pm


Use the format “aged [age] years”

aged nine years

Use the format “aged [age] to [age] years”.

aged 10 to 11 years

Include the months or weeks for ages under a year.

aged nine weeks

If you refer to ages as “[age]-year-old”, include the hyphens.

16- to 24-year-old men

Write decades as an age as numerals.

women in their 40s

Limits for age restrictions should use “aged [age] years and over” or “aged under [age] years”. Do not use the plus sign.

aged 75 years and over

aged under 18 years


Use the major currency unit before the amount. Do not use decimals unless using smaller units.


In a sequence of numbers, use the same number of decimal places, even if every number does not have a smaller unit.

£10.43 rising to £12.00.

Do not use “0.xx million” for amounts less than 1 million, unless in a sequence of numbers.

£3.5 million, £6.5 million and £0.9 million

Write out the smaller unit in full.

15 pence

Currency should use lower case.

The euro is stronger than the pound.

Write out currency as “British pounds”, or “American dollars”.

Measurements and units

Use metric units of measurement, except in specific cases where imperial units are still used as standard.

feet and inches
pints (for beer, cider and milk)
acres (for land registration)

Write out measurements at first mention, then abbreviate. If it is only mentioned once, do not abbreviate.

12 kilometres per hour (kph)

Abbreviations should not have full stops and are always singular. Use a space between the number and the abbreviation, except with one-letter abbreviations.

Write out “miles” and “metres” in full.

12 kph
10 miles

We are constantly improving based on research and best practice. Any significant changes to our guidance are available on the Updates page.

Telephone numbers

When writing telephone numbers, remove the leading zero from the number and replace it with the UK’s international dialling code: +44. Add a space between this code and the rest of the number. 

You should not: 

  • include the zero you’ve removed in brackets; this is particularly important for accessibility as it can affect how some assistive technology reads the number  
  • use 00 instead of + (it does not work from all countries) 

0345 601 3034 should be written as +44 3456 013034
01633 456900 should be written as +44 1633 456900


+44 (0)345 601 3034 or 0044 3456 013034
+44 (0)1633 456900 or 0044 1633 456900

 This is in line with the UN’s International Telecommunication Union standards, which are recognised worldwide. 

Superscript and subscript

Do not use superscript and subscript formatting for numbers within text (except in equations properly formatted as such).

For numbers used as footnote markers, write these in full size, preceded by the word “note” and placed in square brackets:

This may be affected by external factors [note 1].

Write numbers in chemical elements at full size, for example: