Free Grammar HelpWordsHow to use an Apostrophe

Apostrophe Use

The use of apostrophes can be simplified down to two things: possession and contraction. Contraction means that things are shortened. In English grammar, a contraction is when we join two words and leave out some letters. The apostrophe represents the missing letters. Sometimes, we leave the letters off the end of a word (or the beginning), so we use an apostrophe there, as well. These are usually informal uses or slang.

The second use of apostrophes is to indicate possession. It may seem confusing that we use apostrophes for possession. What's missing? This problem arose dut to the history of English. We used to have an "e" before the "s" in possessive nouns. At some point, we started leaving the "e" out, and replacing it with an apostrophe. Now we have forgotten about the missing letter and it's mass confusion.

Apostrophes are used for two things:

1. Apostrophes are used to show where a letter or letters have been left off a word.

2. Apostrophes indicate possession.

Apostrophe Error

Apostrophes are not used for plural nouns*

For some reason I can't fathom, people want to put an apostrophe on words that normally end in a vowel when creating a plural. I see it frequently in "video's." On the left, the taco stand has repeated this error four times! Fortunately I was only stopping for coffee.

* When a plural noun is possessive (i.e., more than one share possession; the dogs' bones = several dogs own several bones) the apostrophe comes after the s.

it's vs its

it's vs its can be answered very simply. it's = it is; its = possessive noun.

We are confused because most nouns use an apostrophe for possession. However, the word "it" is a pronoun. The word "it" is the third person singular pronoun for a non-human, non-gendered, noun. It is used like his or hers, which do not require an apostrophe: him, her, it / his, hers, its.

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While the rules for apostrophe use are fairly simple, there are enough variations to make apostrophes the most common grammar error in the English language, in my humble opinion. Here's a handy chart you can print to help with apostrophe use.

The apostrophe is used in contractions and often (but not always) to indicate the possessive case. (The exception is the possessive pronouns.)

When you are finished here, try our apostrophe quiz.

1. Contractions use apostrophes

The apostrophe is used to indicate where some letters or portions of words have been left out especially when two words are joined. Note: the apostrophe represents the missing letters, not the missing space.

Grammatical use of it's or its

(or its')

It's: Meaning: it is

Example: It's a boy!

Its: Meaning possessive case of it

Example: It went to its home.

Common Error: Using "it's" for possession: This is an exception to the rule for use of apostrophes. It's a very common error. The reason that "its" doesn't need an apostrophe is that it's a possessive adjective and possessive adjectives already have the sense of possession built in.

  • The bird is in its nest. (The nest belongs to IT.)
  • It's a nice nest. (It IS a nice nest.)
  • It's made out of sticks. (It IS made out of sticks.)

Note: Its' is NEVER used. I saw a recent comment on a blog where the writer claimed that some English speaking countries used its'. He didn't state whether or not this was supposed to represent the possessive adjective its, but one would have to assume that it was, since it doesn't make sense, in terms of how we use apostrophes, to assume it meant "it is." (Nor did he specify which English speaking countries he was referring to, so we could check out this unusual assertion.) But using logic, we can see that this must still be false. Possessive adjectives never use apostrophes. We never write her's or their's. (Acutally some of us do, but they're wrong!) By this logic, its' is also wrong. Additionally, we put the apostrophe after the s only when it's a plural. So on another level its' must be wrong because even the worst English speaker knows that "it" is a singular concept.



Meaning: he is (used for 'he has' informally, not usually appropriate for formal writing)

He's learning English online.

He's learned English online. (informal)


Can't, Don't, Won't, Isn't, couldn't, wouldn't,shouldn't

Note: all the words joined with 'not' end in "n't ". The apostrophe represents the elimination of the "o" and we don't need anything to represent the elimination of the space between the words.

I can't buy a computer today.


refers to something which belongs to them

Example: We went in their car to the college.


refers to something which belongs to them

Example: that car is theirs

Note: No apostrophe for the personal pronouns


Meaning: There is

Example: There's the bus!

Common Error: Mistaking there's and theirs


Meaning: they are

Example: They're over there in their car.

Common Error: Mistaking they're, there and their. See misused words page for correct usage of all three.


Meaning: Who is

Common Error: Whose, which refers to possession

Example: Who's there?

The boy whose parents died.

Your, not you're

When something belongs to you

Example: It's your car.

Yours, not your's

When something belongs to you

Example: Take it, it's yours

Note: personal prounoun never take an apostrophe.


Meaning: you are

Example: You're going to love this.

Common Error: Using "you're" when you should use "your" for the second person possessive. Remember, the apostrophe reminds you that there's something left out.

2. Possessive use of apostrophes

An apostrophe is used to indicate the possessive case.

An apostrophe before the s is used to indicate possessive case

Frank's dog.
Frank's dog's bone.
Exceptions: It's = it is so use "its" for possessive.
Example: It's Frank's dog. Frank's dog chews its bone.

An apostrophe is used after the s if the word is plural

If Frank has two dogs and they share some bones then:

It's Frank's dogs' bones.

In fact, if we just followed the rule of 's to indicate possessive it would be easy:

It's Frank's dogs's bones.

But try pronouncing dogs's, and you can see why English speakers simply ended up dropping the extra s, and just write the words with the apostrophe.

Below, I explain that the same factor makes it allowable to drop the final s when a proper name ends in s and the pronounciation of apostrophe + s would be difficult.

An apostrophe is used after the s when the noun ends in s and the addition of another s is awkward. (This is a judgment call and can go either way, depending on the writer.)

Example: The Smith's house is beside the Jones' house
Example: It's the Raiders' ball on the 10 yard line!
Example: I took a big bite out of the octopus' tentacle and he didn't like it! (Alternative: I took a big bite out of the octopus's tentacle and he didn't like it!)

Note: An apostrophe is never used after the s in its.