Using Apostrophes (Grammar and Punctuation)

The Quick Answer
Apostrophes are used:
  • To show possession (e.g., one dog's kennel , two dogs' kennel )
  • In time expressions (e.g., a day's pay , two weeks' holiday )
  • In contractions (e.g., can't , isn't , don't )
Apostrophes are not used:
  • To show plurals (e.g., three cat's , two video's )
  • Randomly before the letter s (e.g., He like's pies. )

Rules for Using Apostrophes

This page explains how to use apostrophes and covers the misuse of apostrophes. Here is a video summarizing the use of apostrophes:

Using Apostrophes for Possession


Apostrophes are used to show possession. For example:
  • The dog's kennel
  • The dogs' kennel
Does the apostrophe go before or after the s?

The big question is whether to put the apostrophe before the s or after the s. The basic rule is this:
The apostrophe goes before the s for a singular possessor (e.g., one dog's kennel) and after the s when it's more than one possessor (e.g., two dogs' kennel).

Be aware that dog and dogs are the possessors. The position of the apostrophe has nothing to do with kennel. That word can be singular or plural. It makes no difference whatsoever to where the apostrophe goes. For example:
  • One dog's dinner
  • One dog's dinners
  • Two dogs' dinner
  • Two dogs' dinners
The apostrophe-placement ruling seems quite straightforward, but there are exceptions.

An exception to the rule: plural words that don't end s

The most notable exception is when the plural doesn't end in s (e.g., children, women, people, men). These words have the apostrophe before the s (even though they're plural). For example:
  • children's toys
  • women's hat
    • (Here's another issue. It's not always about possession. This means a hat for women. Similarly, Picasso's painting is a painting by Picasso. He doesn't own it. Sometimes, it's about "possession" in the loosest terms.)
  • people's poet
  • men's sizes
Another exception to the rule: singular words that end s

Another quirk is that singular nouns ending s (e.g., Wales, Moses, John Wells) form their possessive forms either by adding ' (just an apostrophe) or 's depending on how you (personally) say the possessive form. For example:
  • John Wells' report
    • (This is correct. It is used by those who would say John Wells report as opposed to John Wellsiz report.)
  • John Wells's report
    • (This is also correct. It is used by those who would say John Wellsiz report.)
Be aware that some style guides state you can't use the 's version for religious characters. So, if you're talking about the likes of Jesus or Moses, you might want to opt for the Jesus' and Moses' versions as opposed to Jesus's and Moses's.


Read more on apostrophes to show possession.
(This page covers the possessive form of compound nouns and joint ownership.)

Possessive Apostrophes in Less Than a Minute

Here is a very short video summarizing how to use possessive apostrophes:

Using Apostrophes Incorrectly with Plurals


Don't add an apostrophe to a word just because the word ends with the letter s. This is a common mistake, and it is a grammatical howler. (In other words, your readers will think you're a bit dim if you keep doing it.)

This mistake is most commonly seen when people form the plurals of nouns, but it happens with verbs too; e.g., He eat's pies.

Examples:
  • I like pig's. Dog's look up to us. Cat's look down on us. Pig's treat us as equal's.
    • (These are all wrong.)
  • I like pigs. Dogs look up to us. Cats look down on us. Pigs treat us as
    equals.
  • A spoken word is not a sparrow. Once it fly's out, you cannot catch it.
    • (This mistake is sometimes made with verbs too. This should be flies.)
  • Tomato's and oregano make it Italian; wine and tarragon make it French; garlic makes it good.
    • (This mistake is particularly common when forming the plural of a noun which ends in a vowel (e.g., video's , banana's ). It should be tomatoes in this example.)
Read more on apostrophes used incorrectly with plurals

Using Apostrophes in Time Expressions


Apostrophes can be used in time expressions (also called temporal expressions) like a day's pay and two weeks' notice.

The big question with these is where to put the apostrophe. The ruling is quite simple: the apostrophe goes before the s for a single unit of time (e.g., one day's pay) and after the s when it's more than one (e.g., two days' pay).

Examples:
  • I never did a day's work in my life. It was all fun. (Thomas Edison, 1847-1931)
  • It's not worth it for just two minutes' pleasure.
It's not always about time. For example:
  • I live a stone's throw away.
Don't think you have to use an apostrophe every time you write seconds, minutes, hours, days, weeks, months, etc. Only use an apostrophe where the word of could have been used.
  • a year's insurance
    • (a year of insurance)
  • two weeks' holiday
    • (two weeks of holiday)
Read more on apostrophes used in time expressions

Using Apostrophes to Replace Letters


An apostrophe can be used to replace a letter or letters (e.g., isn't, can't). The new word formed is called a contraction. Contractions are not usually used in formal correspondence.
  • When I was born I was so surprised I didn't talk for a year and a half. (Gracie Allen, 1906-1964)
  • Life is something that happens when you can't get to sleep. (Fran Lebowitz)
Contractions are most commonly used in informal writing to reflect how we speak. These two contractions are notorious grammar villains: it's and you're.

Read more on apostrophes replacing letters

Using Apostrophes in Unusual Plurals


The first thing to say about this topic is that apostrophes are not normally used to show plurals, and lots of your readers will hate it if you use an apostrophe for this purpose. However, that said, there are times when it helps to use an apostrophe to show a plural. For example:
  • There are two i's in skiing.
  • You use too many but's in your writing.
Of course, there are other ways of writing these. For example:
  • There are two Is in skiing.
  • You use too many "but"s in your writing.
The bottom line is apostrophes can be used in this way and for good reason — the apostrophe version is usually neater and clearer. However, be aware that you run the risk of annoying a high proportion of your readers if you do it.

Read more on apostrophes used to show unusual plurals

See Also

Apostrophes for possession Apostrophe placement rules Apostrophe after s Apostrophe after z Apostrophe before s Apostrophes for awkward plurals Apostrophes after acronyms and abbreviations Apostrophes in contractions Apostrophes in expressions like 2 years' pay and a day's notice Apostrophes used incorrectly for plurals Apostrophe exercises Apostrophes in names Apostrophe misuse Apostrophes in contractions Brackets Colons Commas Dashes Hyphens Semicolons Quotation Marks