When to Use Apostrophe S ('s) | Guide & Examples

An apostrophe followed by an “s” is used in English to create possessive nouns. For example, the noun dog becomes dog’s when you refer to something belonging to the dog, such as “the dog’s ball.”

With plural nouns ending in “s,” you add the apostrophe after “s” and do not add an additional “s.” For example, the plural noun parents becomes parents’ (not “parent’s” or “parents’s”) in a phrase like “my parents’ car.”

An apostrophe can also be used to indicate a contraction (shortening of a word or phrase). So an apostrophe “s” may instead be short for the word “is” or “has,” as in “it’s” (“it is” or “it has”). In this context, it doesn’t indicate possession.

Apostrophe “s” to form possessive nouns

An apostrophe followed by an “s” is the most common way to indicate possession (ownership) in English. This applies to most singular nouns and also to plural nouns that don’t end in “s” (e.g., “women” becomes “women’s”).

It also applies to singular nouns that end in “s” (e.g., “the analysis’s implications“), acronyms (e.g., “the BBC’s funding”), proper nouns (e.g., “Jack’s cat”), and compound nouns (where the apostrophe “s” is always added to the final word: “his brother-in-law’s motorbike”).

Exception: “For goodness’ sake”

An exception is usually made in expressions like “for goodness’ sake.” Here, the “s” is left out (even though “goodness” is singular) to avoid having an awkward series of “s” sounds in one place.

The same applies to other singular nouns ending in an “s” sound when they are used before “sake.” The other common examples are “for conscience’ sake” and “for appearance’ sake.”

Names ending in “s”

There’s some disagreement about whether to add the extra “s” for the possessive form of names ending in “s”: for example, do you write Darius’ or Darius’s?

Language authorities differ in their recommendations, but since styles guides like MLA, APA, and Chicago recommend adding the “s,” we advise going for this approach (e.g., “Darius’s reign”).

Note that adding an apostrophe before the existing “s” without adding an extra “s” (e.g., “Dariu’s”) is always wrong.

With words in italics or quotation marks

When forming the possessive of a noun that’s written in italics (e.g., the title of a book or movie), the apostrophe “s” should not be in italics, because it’s not part of the title. Write the apostrophe and the “s” without any special formatting.

• The Great Gatsby’s themes

If the noun is written in quotation marks (e.g., the name of a short story or a song), the combination of quotation marks and apostrophe is hard to read and should be avoided. Form the possessive in a different way, such as by using “of,” in these cases.

• “The Tyger”’s rhyme scheme
• “The Tyger’s” rhyme scheme
• The rhyme scheme of “The Tyger”

Check for common mistakes

Use the best grammar checker available to check for common mistakes in your text.

Fix mistakes for free

Apostrophe after “s” for possession with plural nouns

Plural nouns that end in “s” (most plural nouns) form the possessive with an apostrophe after the “s,” without adding a second “s.”

For example, to describe the roofs of multiple houses, you would write “the houses’ roofs” (“the house’s roofs” would refer to multiple roofs on one house).

This also applies to nouns that look plural even though they’re singular in function (e.g., “politics’ importance,” “the United States’ foreign policy”) and to pluralized versions of names (e.g., “the Johnsons’ car”).

No apostrophe “s” in possessive pronouns

Unlike possessive nouns, possessive pronouns do not contain apostrophes. The possessive pronouns are mine, ours, yours, his, hers, its, theirs, and whose.

It’s important not to add an apostrophe to these words, especially when they can be easily confused with contractions:

• The cat licks it’s fur. [“it is/has fur”?]
• The cat licks its fur.

• I’m not sure who’s this is. [“who is/has this is”?]
• I’m not sure whose this is.

Other forms such as “our’s,” “your’s,” “her’s,” and “their’s” simply aren’t real words.

Apostrophe “s” as a contraction of “is” or “has”

You’ll also commonly see an apostrophe followed by an “s” used to indicate a contraction of “is” or “has” with the previous word. You can tell which word it’s short for based on the context (e.g., “my car’s [car is] not very fast”; “my car’s [car has] got a few dents”).

“Is” and “has” can be contracted with just about any noun (and with many pronouns), so it’s occasionally difficult to see at first glance whether something is a possessive noun or a contraction. Again, the context of the sentence will make it clear what is intended.

As mentioned in the previous section, apostrophes are not used in possessive pronouns, so “who’s” and “it’s” are always contractions, not possessives.

Check for common mistakes

Use the best grammar checker available to check for common mistakes in your text.

Fix mistakes for free

No apostrophe before “s” for plurals

In almost all cases, you should not add an apostrophe before the “s” when you’re simply pluralizing a noun. For example, the plural of “mango” is “mangos,” not “mango’s.”

This common mistake is sometimes called the “grocer’s apostrophe,” based on the fact that you’ll often encounter it on signs in shops and markets.

People are particularly likely to believe an apostrophe is needed when pluralizing nouns ending in vowel sounds (e.g., “frisbee’s”), numbers or decades (e.g., “1980’s”), surnames (e.g., “Jones’s”), or acronyms (e.g., “TV’s”), but the apostrophe is wrong in all of these contexts. The correct forms are “frisbees,” “1980s,” “Joneses,” and “TVs.”

Exception: Pluralizing letters

There is one context in which style guides do advise adding an apostrophe for a plural. This is when you’re pluralizing an individual letter.

In this case, the result of just adding an “s” without any punctuation can often be mistaken for another word (e.g., “is”) or simply look wrong (e.g., “ss”). So it’s standard to add an apostrophe in this context.

Some style guides instead advise italicizing the letter (but not the following “s”): “two es.”

Worksheet: Possessive apostrophe

Want to test your understanding of when to add an apostrophe “s” and when to add just the apostrophe? Try the worksheet below. In each sentence, fill in the correct possessive noun (ending in ’s or just ’) based on the noun presented in brackets.

Other interesting language articles

If you want to know more about commonly confused words, definitions, common mistakes, and differences between US and UK spellings, make sure to check out some of our other language articles with explanations, examples, and quizzes.

Frequently asked questions

When do you put the apostrophe after the “s”?

When forming the possessive of a plural noun that already ends in “s,” you should add an apostrophe after “s” and not add an extra “s.” For example, the plural noun houses becomes the possessive noun houses’.

This is different from forming the possessive of a singular noun (e.g., “house”) or an irregular plural noun that doesn’t end in “s” (e.g. “men”). In those cases, you add an apostrophe followed by an “s”: house’s; men’s.

Is its or it’s possessive?

Its and it’s are often confused, but its (without apostrophe) is the possessive form of “it” (e.g., its tail, its argument, its wing). You use “its” instead of “his” and “her” for neuter, inanimate nouns.

What’s the possessive of a name ending in “s”?

You normally form a possessive noun from a singular noun by adding an apostrophe and an “s,” but there’s disagreement about how to form the possessive of a name like “James.”

Most style guides recommend adding the apostrophe and “s” like normal: James’s. But some argue that it should depend on which version feels most natural to pronounce, so that you could instead write James’, without the additional “s.”

We recommend the first approach, adding the “s” consistently, as it’s recommended by most authorities. Whatever you choose, be consistent about how you form the possessive of a particular name. Don’t write James’ at some points and James’s at others.

What is a possessive noun?

A possessive noun is a noun like “farmer’s” that is used to indicate ownership (possession). It normally comes before another noun that indicates the thing possessed (e.g., “the farmer’s pitchfork”).

Possessive nouns are formed from regular nouns by adding an apostrophe followed by an “s,” or, in the case of plural nouns that already end in “s,” by just adding an apostrophe.