Apostrophes: Grammar Rules For Showing Possession

Mar 16, 2008 | Grammar and Usage, Proofreading, Punctuation

Apostrophes: Grammar Rules For Showing Possession

Updated June 2023

Wondering when a noun should use s, s’, ’s, or es to show possession? Want to know when to use the  apostrophe and when to skip it? Here are some grammar rules (from our proofreaders!) to guide you as you tell ’em whose it is (to show ownership).

Rule 1: To form the possessive of a singular noun that does not end in s or an s sound, add an apostrophe plus s to the noun:

Examples: the doctor’s orders, the writer’s desk, Tammy’s car, my sister’s children, her father-in-law’s house

Rule 2: To form the possessive of a singular noun that does end in s or an s sound, add an apostrophe plus s to the noun:

Examples: Jennifer Lopez’s music, the witness’s report, James’s poetry

One exception to this rule is to add only an apostrophe when adding the apostrophe plus s makes the word difficult to pronounce:

Examples: Sophocles’ plays, Mrs. Rogers’ new car

Rule 3: To form the possessive of a plural noun that ends in s or es, add only an apostrophe to the noun:

Examples: the actors’ roles, the writers’ convention, their doctors’ orders, the beaches’ cleanliness

Rule 4: To form the possessive of a plural noun that does not end in s or es, add an apostrophe plus s to the noun:

Examples: her children’s toys, the women’s dressing room

Rule 5: To indicate separate possession, add whichever possessive sign is appropriate (an apostrophe plus s or an apostrophe alone) to the name of each person:

Examples: Bill’s and Tom’s cars (two separate cars: Bill’s car and Tom’s car), James’s and Olivia’s houses (two separate houses: James’s house and Olivia’s house)

Rule 6: To indicate joint possession, add the appropriate possessive sign (an apostrophe plus s or an apostrophe alone) to the final name:

Examples: Mary and John’s house (the house belongs to both Mary and John), Edward and Madeleine’s books (the books belong to both Edward and Madeleine)

One exception to this rule occurs if one of the owners is identified by a pronoun (my, his, her, our, their). In this case, make each name and pronoun possessive:

Example: Erica’s and my project (not Erica and my project); Mark’s and our dinner (not Mark and our dinner); John’s, Edgar’s, Lisa’s, and my party (not John, Edgar, Lisa, and my party)

A note about the possessive pronouns: my, mine, your, yours, his, her, hers, its, our, ours, their, theirs, whose. These pronouns never require apostrophes.

Rule 7: To form the possessive of a singular abbreviation, add an apostrophe plus s.

Examples: the FAA’s ruling, the MD’s diagnosis, USA’s stand

Rule 8: To form the possessive of a plural abbreviation, add an s’.

Examples: the PhDs’ dissertations, the RNs’ orders, the CPAs’ convention

A note about apostrophes in contractions: Whenever a word or phrase is shortened by contraction, remember to place an apostrophe at the point where the letters are omitted.

Examples: don’t (do not), can’t (cannot), rock ‘n’ roll (rock and roll), ma’am (madam)

Apostrophe placement in first and last names, abbreviations, and pronouns shouldn’t give you any trouble if you just follow these simple writing rules. But if you’re not sure, Writer’s Relief proofreaders may be able to help. So when Maria parks her car in Tom and Jane’s driveway, which is next to the Petersons’ house and across the street from Edward’s and Alfred’s apartments, you’ll have no trouble at all conveying that information to your reader!

When you’re ready to submit your short prose or poetry to literary journals or a novel to literary agents, the experts at Writer’s Relief are here to help! Our research team will pinpoint the best markets for your work and boost your odds of getting published. And that’s a pretty compelling reason to learn more about our services and submit your work to our Review Board today.

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