How to Use Apostrophes

Details below, but here are some cheat sheets for one of the most common apostrophe mistakes.

There are two main uses for apostrophes:

  1. To indicate possession
  2. To form contractions


To Indicate Possession

Most of the time, all you need to do is add an apostrophe and the letter s. (See exceptions below.)

This is Private Pyle's rifle.

This is not just anyone's rifle.

Did you curse the children's toys?

Welcome to the women's ward.

What about words or names that end in the letter s? Yup! Still add 's (exceptions below).

The virus's rate of mutation seems to be increasing.

James's head was missing.

Jess's dog probably buried it in the yard.

For compound nouns, the 's is added to the end of compound noun.

I found a head in my brother-in-law's car.

To indicate shared ownership, add the 's to the last noun.

Jack and Jill's parents were eaten by zombies. (They share parents; they are siblings.)

To indicate individual ownership, add 's to each noun.

Jack's and Jill's parents were eaten by zombies. (They have different parents; they are not siblings.)


There are two instances when instead of adding 's you add only an apostrophe and no s.

1. Plural nouns ending in s

We can hide out in my parents' basement. (The basement belongs to both parents.)

We'll have to eat some of the dogs' food. (There are multiple dogs.)

2. Singular nouns ending in s that are the same when plural

This species' DNA is like nothing we've ever seen before.

Other singular nouns ending in s that are the same when plural: pants, scissors, shorts, series, tweezers, news. Words like these have the same possessive form whether singular or plural (apostrophe only).


To Form Contractions

To form contractions, an apostrophe is used in place of letters.

did not → didn't
have not → haven't
running → runnin'
nothing → nothin'
rock and roll → rock 'n' roll


Other Uses for Apostrophes

To pluralize lower case letters, add an apostrophe and an s. This is rare, but it may come up; for example, if you are teaching someone how to spell a word. 

"Horror" is spelled with two r's.


Common Mistakes

Its vs. It's and Whose vs. Who's

Which are correct?

a. It rubs the lotion on its skin.
b. It rubs the lotion on it's skin.

c. Whose turn is it to bury the bodies?
d. Who's turn is it to bury the bodies?

It and who are both examples of pronouns (words that take the place of nouns). Other examples of pronouns are I, We, They, She, He.

Possessive pronouns never use apostrophes (e.g., his, her, your, my, our, their, its, and whose).

It's is a contraction for it is, and who's is a contraction of who is; therefore, answers a and c are correct.