Thompson Rivers University
Thompson Rivers University

Numbers

General rules

In running text, spell out numbers one through nine. For 10 and above use numerals.

Always use numerals for:

  • measurements that use abbreviations or symbols, e.g. 5 km, 2 L, 9˚C
  • percentages, e.g. 50%
  • quantities consisting of whole numbers and fractions, e.g. 1½
  • course units, e.g. (3)
  • grade-point averages, e.g. 4.33
  • currency, e.g. $5

One important exception: always spell out numbers that begin sentences.

For numbers in official names, follow the organization’s spelling style even when it is at odds with TRU practice.

Ordinals

The above practices apply to ordinal numbers as well. Spell out ordinal numbers when referring to year of study.

Surita is in her fourth year of study.

When using the abbreviated form of ordinals, place numerals and letters on the same line. Do not use superscript.

45th anniversary

Streets that are named with ordinals should also follow the general rule.

Third Street, 37th Avenue

Numbers with four or more digits

In numerals with four or more digits, use commas to separate groups of three digits except house, telephone, page, year and other serial numbers.

1,200; 1198 Columbia Street; 1-800-828-5000

Very large numbers can use a mixture of numerals and spelled out numbers.

2.3 million, 458 billion

Currency

Always use numerals to express currency. Canadian currency is expressed in numerals accompanied by the appropriate symbols ($ and ¢). There is no space between the currency symbol and the numeral.

Two second-year arts students were awarded $5,000.

Note that zeros after a decimal point should only be used if they appear in context with other fractional amounts.

Prices ranged from $0.95 to $1.00.

Very large amounts may be expressed with a mixture of numerals and spelled-out numbers and should appear with the currency symbol.

$4 million, $8.97 billion

When referring to foreign currency in specific numerical amounts, use the three-letter currency code (in upper case) instead of the currency symbol.

USD 42.78
EUR 123.00

Decimals

Use a zero before a decimal point when the value is less than one.

0.5, –0.62

Fractions

Use fraction characters (or superscript/subscript) whenever possible instead of full-sized numerals separated by a slash.

not 8 1/2

Simple fractions that are not mixed numbers should be spelled out.

the first half of the semester; one third of students

When a fraction is considered a single quantity, it is hyphenated.

She has read three-quarters of the book.
This is a half-hour lecture.

However, when the individual parts of a quantity are in question, the fraction is spelled without the hyphen.

We cut the sample into four quarters.

Quantities consisting of whole numbers and fractions should be expressed in numerals.

8½ x 11 in. paper

Percentages

Percentages should be given in numerals. If the text includes numerous percentage figures, the symbol % is appropriate. Otherwise, use the word “percent”. In tables, it is acceptable to use the symbol.

The minimum grade required in English 12 varies from 67% to 80%.
Ten percent of students are Aboriginal and over 14 percent are international.

There is no space between the numeral and the symbol %. In the second example, "Ten" is spelled out following the general rule to always spell out numbers that begin sentences.

Plurals of numerals

Spelled-out numbers form their plurals like other nouns.

the terrible twos
Bad things always happen in threes. 

Ranges (inclusive numbers)

An en dash (a dash slightly longer than a hyphen) between two numbers implies “up to and including” or “through”. 

Please refer to pages 45–72.

See Punctuation and spelling: Dashes and hyphens.

If “from” or “between” is used before the pair of numbers, the en dash should not be used; instead, “from” should be followed by “to” or “through”, and “between” should be followed by “and”.

from 45 to 63
between 1898 and 1910 

Measurements

In general, spell out metric units of measurement in running text: litres, kilometres, minutes. If an abbreviation or symbol is used for the unit of measure, the quantity is always expressed as a numeral.

Metric symbols

Metric units of measurement are symbols, rather than abbreviations, with a space before and no period after. Metric symbols are in lower case except for litres, which uses a capital L to avoid confusion with the numeral 1.

5 km, 20 ml, 9 L

Abbreviating imperial measurements

Customary (imperial) units of measurement are abbreviations, and should appear in lower case, with a space before and a period at the end of each unit. In running text, use the abbreviations "ft." and "in." rather than using a single quotation mark for foot and double quotation marks for inch.

6 in., 24 ft., 36 sq. in., 12 mi., 5 lb.

Temperature

Celsius is abbreviated as a capital.

It was 28˚C yesterday.

Using superscripts

Square measures may be expressed as "sq m" or with the superscript: "m2". The latter form is to be used in scientific or technical text. Cubic measures should be expressed using the superscript. 

6 m3

Roman numerals

Monarchs, emperors and popes with the same name are differentiated by Roman numerals.

Elizabeth II, Louis XIV

Roman numerals are also used to designate the sequel to a novel or movie.

Rocky IV

Telephone numbers

Domestic telephone numbers should be separated with hyphens. No parentheses should be used around area codes.

250-828-5000

800 numbers should be written as follows:

1-800-828-5000

International phone numbers are expressed in the ITA standard format.

+22 609 123 4567

The international prefix symbol (+) precedes the country code, which is then followed by the area code and telephone number.