Apostrophes in Plurals
Use an apostrophe to form plurals of letters of the alphabet.
- There are two i’s in iridescent.
The plural “i’s” would read as the word “is” without the apostrophe.
- There are two a’s in abacus.
But avoid using an apostrophe before the s in a plural, unless necessary to avoid confusion. Most plural forms don’t require an apostrophe.
- Farley has lost his shoes.
- The Eriksens went to Vietnam last summer.
- She won with a pair of nines.
In names of centuries and decades, the apostrophe is optional, though generally omitted in formal writing.
- the 1800s or the 1800’s
Similarly, although an apostrophe may be used in plurals of abbreviations, numerals, and words that are not nouns, it is usually omitted in formal writing.
- SSNs or SSN’s
- a pair of 9s or a pair of 9’s
- ifs and maybes or if’s and maybe’s
In regular plurals
Don’t insert an apostrophe before s in the standard plural of a noun.
- Incorrect: We have hired thirty new employee’s this year.
Correct: We have hired thirty new employees this year. - Incorrect: The volcano’s have all erupted together.
Correct: The volcanoes have all erupted together. - Incorrect: Rita thinks tarantula’s make for wonderful pet’s.
Correct: Rita thinks tarantulas make for wonderful pets. - Incorrect: We have three pony’s on the farm.
Correct: We have three ponies on the farm. - Incorrect: Don’t sit on my spectacle’s!
Correct: Don’t sit on my spectacles!
In plurals of words that are not nouns
To form the plural of a word not generally used as a noun, add an s or es without an apostrophe.
- I count nine ayes and eleven nays.
- All these ifs, buts, and maybes will get us nowhere.
- It was a funny list of dos and don’ts for how to use a toothpick.
- This pandemic has only widened the gap between the haves and the have-nots.
Don’t use an apostrophe in yeses and noes. These are regular plural forms of yes (a positive answer or vote) and no (a negative answer or vote).
- Incorrect: We counted seven yes’s and five no’s.
Correct: We counted seven yeses and five noes.
Most style guides recommend omitting the apostrophe from plurals whenever possible, as do unabridged dictionaries such as Webster’s. (Modern writing favors a sparser punctuation style.) However, some writers do like the apostrophe, since it can make the plural form of a word not generally used as a noun more readable. This is acceptable in creative writing.
- I don’t want to hear any if’s and but’s.
- The do’s and don’ts are listed in the document.
Dos and don’ts (without apostrophes for the plurals) is recommended by the Chicago Manual of Style, the Oxford English Dictionary, and the Guardian style guide. The AP Stylebook suggests do’s and don’ts (with an apostrophe for the plural only in do’s). Either style is acceptable.
- Chicago: Make a list of dos and don’ts.
AP: Make a list of do’s and don’ts.
In plurals of abbreviations
Avoid using an apostrophe to form the plural of an abbreviation that contains capital letters and no periods.
- We need two MBAs and three CPAs in the team.
- The NGOs have together filed a petition.
- We have two PhDs in the family.
- How many ATMs does this bank have?
- Most CMSs (or CMSes) use our software.
Note that it is not incorrect to use an apostrophe in such abbreviations (ATM’s, PhD’s) but considered inelegant and unnecessary in formal writing.
In plurals of abbreviations that contain internal periods, apostrophes can help improve readability.
- We were asked not to use abbreviations, but I see two “e.g.’s” in this paper.
In some writing styles (especially British), periods are inserted between the capital letters of an abbreviation. An apostrophe is then used to form the plural.
- None of the M.B.A.’s and Ph.D.’s could solve the problem.
- Anita has two B.A.’s and an M.A.
In plurals of letters of the alphabet
Always use an apostrophe to form the plurals of lowercase letters.
- There are two i’s in miniature.
Without the apostrophe (“There are two is in miniature“), this sentence would be confusing.
- The only variables accounted for are the x’s and y’s. What about the z’s?
- It’ll be painful to be on my p’s and q’s for a whole week.
An apostrophe can also help make plurals of capital letters more readable. Using it is optional: the AP Stylebook recommends using the apostrophe; the Chicago Manual of Style suggests omitting it.
- AP: Will the A’s, B’s, and C’s please board the flight?
- Chicago: Do the Xs and Ys really matter?
In plurals of numbers
When numbers are written in words, their plurals are formed like regular English plurals, by adding s or es.
- Without the teacher, the class was all at sixes and sevens this morning.
- They sat in twos and threes, waiting for the band to arrive.
In forming the plurals of numerals, apostrophes are again superfluous.
- Rita has swiped all the 2s and 3s from the game.
- The left-handed batter hit four 4s in a single over.
Some writers prefer to use an apostrophe: 2’s and 3’s. Both styles—with and without the apostrophe—are acceptable.
In decades and centuries
The names of decades and centuries may be written either with or without an apostrophe.
- the 1800s or the 1800’s
- the 1960s or the 1960’s
Most major style manuals (such as the Chicago Manual of Style, the APA Publication Manual, and the AP Stylebook) recommend omitting the apostrophe in names of decades and centuries.
- alternative rock music of the 1990s
- the discoveries of the 1800s
- the hippies of the 1960s
When the century is omitted from the decade, an apostrophe indicates the omission. Inserting another apostrophe before the s is then inelegant.
- Poor: the ’80’s and ’90’s
- Better: the ’80s and ’90s
In plurals of names and surnames
To form the plural of a name, add s or es, without an apostrophe.
- There are four Nesbits in my class.
- We are a group of Lucases trying to save the planet.
- The Smiths have left the planet.
- The Jenningses are getting a new robot.
- Have the Murphys moved to Mars?
The only time you may need an apostrophe to form the plural of a name is when not using one would be confusing. For instance, both Luca and Lucas are names of people.
- Poor: There are three Luca’s/Lucas in my class.
Don’t be afraid to rewrite such a sentence. Better: There are three boys named “Luca” in my class.
In plural place names
Don’t unnecessarily insert an apostrophe before s in place names that are plural.
- Incorrect: We visited the Philippine’s last year.
Correct: We visited the Philippines last year. - Incorrect: Lulu lives in the United State’s.
Correct: Lulu lives in the United States.
Plural names of geographical features also don’t require an apostrophe.
- Incorrect: the Ande’s
Correct: the Andes - Incorrect: the steppe’s of Central Asia
Correct: the steppes of Central Asia - Incorrect: the Isle’s of Scilly
Correct: the Isles of Scilly
In plurals of italicized terms
Plurals of titles of books, movies, and other works (such titles are italicized) are formed by adding an s. No apostrophe is needed before the s. The title of the work is italicized, but the s that forms the plural is not.
- All they have in the waiting room are Washington Posts and Wall Street Journals. Where are the Cosmos?
- She replied, “We already have seven To Kill a Mockingbirds in our library. Could you donate another title?”
- There were about twenty Lancets lying on the table.
Note that in formal writing, an editor would rephrase these sentences, unless quoting someone verbatim.
- She said they already had seven copies of To Kill a Mockingbird in the library.
- There were twenty copies of the Economist lying on the table.
Some writers prefer to use an apostrophe before the s. This is not wrong but less formal. If an apostrophe is used, it should not be italicized but set in roman.
- All they have in the waiting room are Washington Post’s and Wall Street Journal’s. Where are the Cosmo’s?
If an italicized term or title is already in plural form, don’t add another s.
- Over the years, I have bought and lost any number of Anne of Green Gables.
- Several New York Times lay strewn about the study.
In plurals of quoted text
To form the plural of a word or a phrase in quotation marks, place an s within the quotation marks, without an apostrophe. Adding it outside can make the text harder to read.
- I’ve emailed them a thousand times and am tired of all the “Sorry about the inconveniences.”
Easier to read than “Sorry about the inconvenience”s.
- “Sorrys” and “thank yous” don’t solve problems, do they?
- How many “for examples” do you count in the text?
- This series has been ruined by all the “To be continueds.”
Note that rephrasing such sentences is often the better option.
- How many times is “for example” used in the text?
- This series has been ruined by all the episodes ending in “To be continued.”
Using an apostrophe to form such a nonstandard plural is not incorrect, but generally unnecessary.
- How many “for example’s” do you count in the text?
- I’m sick of all their “Sorry about the inconvenience’s.”