Business Writing Center

Tools

The Apostrophe (')

To indicate possession   

  • For most singular nouns, simply add ‘s to make the noun possessive 
    Example: the memo's main point, the bank's president

  • Plural nouns ending in s, simply add an apostrophe  
    Example: twenty thousand dollars’ worth of stock, the classes’ curriculum  

  • Plural nouns not ending in s, add's
    Example: women’s studies  

  • Compound words, make the last word in the group possessive 
    Example: son-in-law’s job, editor-in-chief’s desk 

  • Two or more nouns  
    Make each noun possessive to denote individual possession 
    Example: The report will compare Adam Smith's and Karl Marx's theories.

    Make only the second noun possessive to denote joint possession 
    Example: Ethan Hawke and Uma Thurman’s baby is named Mia.   

To indicate contractions or other word and/or letter omissions

  • Use an apostrophe when you combine (contract) two words into one
    Example: was not = wasn’t, do not = don’t, she would = she’d  

  • Other examples of word omissions: eight o’clock, sugar 'n' spice, class of ’02   

To signal the plural forms of numbers, letters, symbols, and words used as terms   

Example: five 0’s in her income, no F’s on the report card, use #’s to designate numbers     

A common error involving the apostrophe

A common error is the confusion of it’s and its. When in doubt, try reading your sentence aloud, using it is for it’s.   

Example: It’s the most that the department can do to help the project. Read aloud, “It is the most that the department can do to help the project.” The sentence makes sense, so you have a contraction and need the apostrophe. 

Example: The team won it’s third debate in a row. Read aloud, “The team won it is third debate in a row.” The sentence doesn’t make sense, so you don’t need the apostrophe.     

By Margaret Koehler for Goizueta’s Business Writing Center, copyright 2001