Apostrophes

Apostrophes indicate possession, represent letter omission, and indicate certain plurals. These are the universally accepted uses of the apostrophe:

Before S in Possessives

Apostrophes come before an S after a noun or proper noun to indicate that it is possessive.

See Examples

Note: "It's" is a contraction of "it is"; "its" is a possessive pronoun much like "his" or "her."

After Plural Possessives Ending in S

Apostrophes follow a plural noun or plural proper noun that ends in S to indicate that it is possessive.

See Examples

Note: The Merriam-Webster Guide to Punctuation & Style extends this rule to plurals ending in Z.

After the Final Possessor in Joint Possession

If two or more nouns or proper nouns are expressing possession of the same thing, the rules above are applied to the final possessor.

See Examples

After All Possessors in Possession of Similar Things

If two or more nouns or proper nouns are expressing possession of separate things of the same name, the first two rules above are applied to all possessors.

See Examples

For Letter Omission in Contractions

When two words are combined to form a contraction, an apostrophe replaces the omitted letter or letters.

See Examples

Note: "It's" is a contraction of "it is"; "its" is a possessive pronoun much like "his" or "her."

Before S after a Letter, to Indicate a Plural

An apostrophe comes before an S after a letter to show that the letter is plural.

See Examples