The use of numbers in writing is inevitable in our everyday writing, especially in business and academic writings that involve numerical data. Spelling out the number or using figure seems to be asked most often by people as it may be tricky at first if we don’t understand the basic rules. If you want to learn about grammar rules for numbers, then keep reading to find out.
English Grammar Rules for Numbers
Our following discussion about grammar rules for numbers will only scratch the surface, so if you are serious about understanding all the rules, go for a style guide such as The Associated Press Stylebook or The Chicago Manual of Style. Although writing numbers is largely a matter of writers’ preference, fortunately, these general rules for numbers are universally agreed. So, you don’t have to worry about making silly mistakes.
When to spell out numbers in writing?
Most guides recommend spelling out numbers zero through nine.
- Andy has two younger brothers and three older sisters.
I bought three new DVD games last week.
Five crash victims were admitted to the local hospital.
Numbers Beginning a Sentence
When you put a number at the beginning of a sentence, most sources recommend spelling out all the number.
- Four hundred seventy-five people a year die of this disease on average.
Twenty fourteen was quite a year.
However, The Associated Press Stylebook makes an exception for years. It recommends using figures instead of spelled out numbers.
- 2014 was quite a year.
2019 will have some business trends.
When spelling out compound numbers, you should hyphenate all the numbers from twenty-one through ninety-one.
- Forty-three lives were lost in the shipwreck.
Thirty-five students were hospitalized after suspected carbon monoxide leak.
When spelling out fractions, you should hyphenate them.
- Two-third of the money raised by the concert will go to charity.
Our products market share drop to less than one-fourth in the third quarter of the year.
However, avoid hyphenating fraction terms like a half, a third, or a fourth.
When to write numbers in figures?
Numbers 10 and Above
Most guides recommend using figures to write numbers above ten.
- My sister spent a lot of money for 12 dresses and 14 pairs of shoes in the last six months.
However, The Chicago Manual of Style recommends spelling out the numbers zero through one hundred instead of using figures for numbers above ten.
When numbers are in a list, it’s best to write the numbers consistently, even if the list consists of numbers under and over 10.
- Mila has three sisters aged three, seven, and 11. (Inconsistent)
Mila has three sisters aged 3, 7, and 11. (Consistent)
Joe has traveled to five European countries and 12 Asian countries for the last five years. (Inconsistent)
Joe has traveled to 5 European countries and 12 Asian countries for the last five years. (Consistent)
The best way to write a large number is to make it as simple as possible.
- Example: Forty-five hundred sounds simpler than four thousand five hundred.
Large round numbers are often spelled out, but you need to be consistent within a sentence if two or more large numbers come up.
- Flagship phones prices range from one thousand to two thousand dollars. (Consistent)
Flagship phones prices range from one thousand to 2 thousand dollars. (Inconsistent)
Flagship phones prices range from $1 thousand to two thousand dollars. (Inconsistent)
Money is usually written in figures, but it can be spelled out when the amount is rounded up or vague. Put the currency symbol before the numbers without spaces.
- Harry earned $1,375 from his last project.
The 10 chicken nuggets here only cost two dollars.
With four or more digits figures, place commas after every three numbers from right. When counting the numbers, don’t include decimal points.
- 1,567 people
Some writers don’t use commas with the four-digit numbers, but this practice isn’t recommended.
When you reach numbers in the millions and billions, spell out the full word to make it simpler.
- The publishing company earned $12 million in 2017.
When writing out a total of less than a dollar, it’s not necessary to use a decimal point or and dollar sign.
- I only had $0.60 in my pocket. (Inadvisable)
I only had sixty cents in my pocket. (Acceptable)
I only had 60 cents in my pocket. (Acceptable)
Don’t use word “dollar” and dollar sign at the same time. Use one of them and be consistent.
- I have $1,740 dollars in my saving account. (Incorrect)
I have $1,740 in my saving account. (Correct)
The meal only costs three dollars. (Correct)
When spelling out a number of three or more digits, it’s not necessary to put “and”. However, use “and” to express any decimal points that follow.
- Two thousand two hundred seventy dollars.
Two thousand two hundred seventy dollars and forty-six cents.
Twenty-two hundred seventy dollars and forty-six cents. (Simpler)
When spelling out numbers above 999, don’t use commas.
- Three thousand, two hundred twenty-six dollars, and fifty-one cents. (Incorrect)
Three thousand two hundred twenty-six and fifty-one cents. (Correct)
Mixed fractions are often written in figures unless they come at the beginning of a sentence.
- The recipe calls for 2 ½ cups of cocoa powder.
Percentages are usually written in figures unless they come at the beginning of a sentence. Put a space between the number and percent only if they are spelled out.
- The bank charges interest at 3.5%.
The house prices increased by an average of 5.4% annually.
Forty-seven and one-half percent of the population voted for the presidential election.
You can use the word “percent” or sign “%” in everyday writing, both are acceptable. In formal writing, however, you should spell out the percent sign.
Use figures to write decimals. As a courtesy to their readers, many writers put a zero in front of the decimal point.
- The sprouts grew 1.8 inches in three days.
Satellite measurements show that sea level rises 0.11 inch per year.
When you talk about times, you can use noon and midnight rather than writing 12:00 PM and 12:00 AM. It’s done to make it simpler and clearer.
- The burger stand is open from noon to midnight every day.
We left home at noon and arrived there at midnight.
AM and PM also can be written in three different styles: A.M. and P.M.; a.m. and p.m.; and am and pm. Some put a space between the time and AM/PM, while the rest leave it with no space. However, it’s advisable to put a space in between.
- 9 A.M.
Always use numerals with AM and PM.
- The plane leaves at eight-thirty am. (Incorrect)
The plane leaves at 8.30 am. (Correct)
The show starts at seven pm every Monday to Friday. (Incorrect)
The show starts at 7:00 pm every Monday to Friday. (Correct)
Using figures to talk about the time of day has become widely accepted, especially when we need to emphasize the exact time.
- The train departs O’Hare at 09:00 am on Saturday.
We’re meeting at 9:30 sharp.
However, some writers prefer to spell out the time than using figure, especially when using o’clock.
- Joana takes the six thirty-three train from London Euston.
It’s already nine o’clock; you’ll be late for the meeting.
Use figures to express dates.
- Are coming to my birthday party on the 17th of August?
Avoid using ordinal numbers with full dates.
- They are playing an important match against the defending champion on June 23rd, 2018. (Incorrect)
They are playing an important match against the defending champion on June 23, 2018. (Correct)
When spelling out decades, it’s not necessary capitalizing them.
- My favorite band was incredibly successful in the nineties. (Correct)
The U.S. economy grew significantly during the eighties and nineties. (Incorrect)
When using figures to write decades, you can make it simpler by putting an apostrophe preceding the incomplete numeral and don’t another apostrophe between the number and s.
- The U.S. economy grew significantly during the ‘80s and ‘90s.
Some writers put the apostrophe between the number and s.
- The U.S. economy grew significantly during the 80’s and 90’s. (Acceptable)
The U.S. economy grew significantly during the ‘80’s and ‘90’s. (Awkward)
You may also write decades in complete figures, but it’s better to avoid putting an apostrophe between the year and s.
- The U.S. economy grew significantly during the 1980s and 1990s.
Well, that’s all our discussion about grammar rules for numbers. We hope it could help you to aid you to understand when to spell out numbers in writing and use figures. To find more English lessons about basic English grammar rules, punctuation rules, or even text genres, you can click on the category or the related label given.