The possessive case shows the relationship of a noun to other words in a sentence. The relationship can be possession, ownership, or another form of association. In general, to form the singular possessive case of a noun, add an apostrophe “s” to the end of the noun. Both common and proper nouns follow the same principle.
Examples of possessive singular nouns:
Samantha’s dogs
My mother’s alma mater
Stefanie’s brother’s boat
The child’s favorite food
Beyaz’s favorite place to sleep
The house’s windows
The reference’s punctuation
Learn more
Possessive nouns are covered in the seventh edition APA Style manuals in the Publication Manual Sections 4.8 and 6.11 and the Concise Guide Sections 2.8 and 5.1
Singular nouns that end in “s,” including people’s names, can be made possessive by adding an apostrophe “s” to their endings.
Examples of possessive singular nouns that end in “s”:
Ms. Adams’s classroom
Mr. Roberts’s son
James’s journal articles
Descartes’s philosophy
The glass’s glittery design
To make a plural noun ending in “s” possessive, add an apostrophe to the end of the noun.
Examples of possessive plural nouns:
employees’ uniforms
companies’ rules and regulations
health care providers’ ethical considerations
Andohs’ neighborhood
Ortizes’ opinions
United States’ first president
To make plural surnames possessive, as in the “Andohs’” and “Ortizes’” examples in the list above, add the apostrophe after the final “s” as with other possessive plural nouns. For more information on plural surnames, see the Plural Nouns page.
“United States” is plural in form even though it is singular in meaning, so only an apostrophe is needed after the final “s” in “States” to form the possessive, as shown in the example above; this example could also be rewritten as “the first president of the United States.”
Irregular plural nouns that do not end in “s” (e.g., “nuclei”) can be made possessive by adding an apostrophe “s” to their endings.
Examples of possessive irregular plural nouns:
women’s leagues
men’s clothing
children’s toys
people’s money
To show that two or more nouns collectively possess an item, change only the final noun to the possessive case.
Example of the possessive form for multiple nouns that possess the same item:
Anne, Hannah, and Tim’s new cat is really playful.
To show that two or more nouns individually possess the same item, change all the nouns to the possessive case.
Example of the possessive form for two nouns that separately possess items:
Both Chelsea’s and Emily’s lunchboxes are orange.
In rare cases, a proper noun ends in an apostrophe “s” (e.g., the restaurant “Denny’s”). Although you could form the possessive case of these noun types by adding an apostrophe “s” to the end of the noun (e.g., “Denny’s’s pancakes”), this leads to awkward spelling and pronunciation. Instead, it is clearer to reword the phrase or sentence rather than use the double apostrophe “s” (e.g., “the pancakes at Denny’s”).
Abbreviations can also be made possessive in both their singular and their plural forms. Be sure to define most abbreviations on first use. The following examples assume the abbreviations have already been defined elsewhere in the paper.
Examples of possessive singular abbreviations:
NIH’s policies
CDC’s advisory committees
Examples of possessive plural abbreviations:
URLs’ formatting
RNs’ training
Note that in some cases, it may be clearer to reword a sentence than to use a possessive plural abbreviation (e.g., “the formatting of the URLs” or “the training of the RNs”).
The possessive case can also be used with in-text citations. A work with two authors can be made possessive by adding apostrophe “s” after the second name only, not after both names. For a work with three or more authors that is shortened to the name of the first author plus “et al.” (which stands for “and others”), place the apostrophe “s” after “et al.”
Examples of possessive narrative in-text citations:
Yoon’s (2019) study
Curtis’s (2022) investigation
Petrovich and Keefer’s (2023) research
Graver et al.’s (2020) research
Examples of nouns in their possessive form and their meaning are presented next.
| Possessive form | Meaning of possessive form |
|---|---|
|
Cameron’s bike |
The bike that is owned by Cameron |
|
The baby’s blanket |
The blanket that belongs to the baby |
|
Erin’s and Diego’s red cars |
Separate red cars, in which one belongs to Erin and the other belongs to Diego |
|
The Joneses’ dog |
A dog that belongs to the Jones family/a group of Joneses |
|
Marcus and Samara’s mother |
The mother of both Marcus and Samara |
|
Comas-Díaz and Akbar’s (2023) article |
The 2023 article written by Comas-Díaz and Akbar |
|
The girls’ laptops |
More than one laptop that belongs to more than one girl |
|
Jason’s and Mariah’s parents |
The parents of Jason; the parents of Mariah |
|
President Adams’s policies |
The policies of President Adams |
|
The boys’ books |
More than one book that belongs to more than one boy |
|
APA’s databases |
The databases published by APA |