apostrophe

An apostrophe conveys possession in most cases. The rules around apostrophe use change with singular nouns, plural nouns, if a word involves an s sound, or involves joint or multiple people possessing another object. It is best to check the rules when unsure of when to use an apostrophe.

Add an apostrophe followed by an s to:

• singular common nouns not ending in s (even if they end in an s sound such as -ce, -x, and -z)
• singular common nouns ending in s (unless the next word begins with an s)
• plural common nouns not ending in s
• compound words – add the apostrophe and s to the word closest to the object possessed, example: the surgeon general’s press release, the attorney general’s case
• joint possession – add the apostrophe and s after the word or name if ownership is joint, example: Jamie and Alex’s bookstore
• individual possession – add the apostrophe and s after both words or names if ownership is individual (example: Jamie’s and Alex’s books)
• double possessives – the word after of takes an apostrophe and s when (1) the word after of is an animate object and (2) the word before of is only a portion of the object’s possessions. Example: a friend of Jamie’s or a sibling of Alex’s
• for plurals of a single letter, example: every reporter knows the five W’s and one H or she got all A’s on her report card.

Add only an apostrophe, but no s, to:

• singular common nouns ending in an s when the next word begins with an s
• singular proper names ending in an s
• plural nouns ending in an s
• nouns plural in form and singular in meaning, for example: mathematics’ rules, measles’ effects
• to replace omitted letters, for example: rock ‘n’ roll, ’tis the season, ne’er-do-well, etc.
• in a contraction, for example: I’ve, you’re, it’s, don’t, etc.
• in omitted figures, for example: class of ’98, the Roaring ’20s

Special rules:

• Nouns the same in singular and plural form, such as corps, moose, deer, fish, etc., are treated by plural rules: one corps’ location, two moose’s tracks, five deer’s antlers, one fish’s fin.
• St. James’s Palace always gets an apostrophe and s.
• The phrases appearance’ sake, conscience’ sake, and goodness’ sake all use only an apostrophe without an s, but other special expressions generally use an apostrophe with an s.
• Personal interrogative and relative pronouns do not use an apostrophe: mine, ours, your, yours, his, hers, its, theirs, whose.
• Some governmental, corporate, and organizational names use an apostrophe in their names and some do not. Follow their practice in how they use the apostrophe in their name, for example: Ladies’ Home Journal, National Governors Association, Actors’ Equity, etc.

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