The invitation arrived on heavy cream card: "Dinner and dancing to follow at the Henderson's." A lovely couple, a beautiful venue. The apostrophe, though, is quietly doing damage. It turns "Henderson" into one person who owns something called a dinner, when the couple almost certainly meant the Henderson family's home, or possibly just their own surname, plural, with no apostrophe anywhere. On the most photographed day of their lives, they misspelled themselves.
The apostrophe has exactly two jobs: marking possession ("the author's contract") and marking the letters that vanished from a contraction ("don't"). That is the entire portfolio. Nearly every apostrophe error in the wild, from shop signs to annual reports, comes from assigning the mark a third job it has never held: making plurals.
Two jobs, and only two
| Job | Example | What the mark is doing |
|---|---|---|
| Possession | the client's briefcase, a week's notice | showing whose, or how much |
| Contraction | don't (do not), we're (we are), rock 'n' roll (and) | standing in for missing letters |
| Nothing else | bagels, Sundays, CDs | plurals take no apostrophe |
That third row is the rule people break, so it belongs in the table even though it isn't a job. Readers can't see what you meant by a stray apostrophe. They can only see what the sentence now says, which is usually something you didn't intend.
Singular possession, including the awkward names
The easy case first: for one owner, add 's. "The manager's decision." "A week's notice." "The witness's account." Then the names ending in s arrive, and the style camps split:
- Chicago style, used in book publishing and most formal documents, adds 's regardless: "Chris's report," "the bass's lowest note."
- AP style, used in journalism, typically takes the bare apostrophe for names ending in s: "Chris' report."
Both are correct within their systems. Neither is correct when you alternate, because readers can't tell a convention from a guess. Classical names get a narrow dispensation in most guides: "Jesus' teachings," "Moses' staff," "for goodness' sake." These are pronunciation decisions more than grammar. The extra syllable in "Chris's" says itself easily; "Jesus's" fights the tongue.
Plural possession, where invitations go to die
Plural possession is a two-step process that nearly everyone attempts in one. Step one: make the noun plural. Step two: add the apostrophe. "The Smiths' garden" means the garden of the Smiths, all of them. "The Smith's garden" means the garden of one individual named Smith, perhaps the gardener.
The tripwire is step one, because family names pluralize by sound, not by instinct:
| Name | Plural | Possessive |
|---|---|---|
| Kennedy | the Kennedys | the Kennedys' porch |
| Jones | the Joneses | the Joneses' annual letter |
| Martinez | the Martinezes | the Martinezes' restaurant |
| Wolf | the Wolfs | the Wolfs' cabin |
That last row surprises people. Proper names decline regularly: the family named Wolf are the Wolfs, never the Wolves, because irregular plurals belong to common nouns. "Merry Christmas from the Joneses" is correct, and it is almost never written correctly.
Irregular plurals reverse the flow. "The children's hour," "women's sizes," "men's room": the plural doesn't end in s, so the possessive adds 's as if it were singular. English pays out this reward only to people who already know the exception.
One last wrinkle, shared versus separate ownership:
Its and it's, the heavyweight bout
No error appears more often in otherwise professional writing, and the rule is one sentence long. Possessive "its" takes no apostrophe, because it belongs to the family of possessives that never had them: his, hers, ours, yours, theirs. Contractions take the apostrophe because letters are missing. "It's" means "it is" or "it has." That is the whole distinction.
"The company changed its logo." Possessive. No apostrophe. "It's the third redesign this year." Contraction: it is.
The repair is mechanical. Every time you write "it's," expand it in place. If "it is" or "it has" doesn't fit the sentence, you wanted "its," and the error dies on the spot. If a draft is already infested, a find and replace pass will line up every instance for judgment. Its/it's is only the most famous of the sound-alike traps; the confusable crew behind their, there, and they're works the same streets.
The greengrocer's apostrophe
"Fresh bagel's." "Open Sunday's." "Chip's and dip." The shop window is where the plural apostrophe does its most visible work, so consistently that the error is named for it: the greengrocer's apostrophe, the practice of marking any plural with a stray 's, especially after vowels, abbreviations, and numbers.
The rule is blunt. Plurals do not take apostrophes. "Bagels," "Sundays," "chips," full stop. An apostrophe appears with a plural only when something is possessed ("the bagels' sesame crust," and note it sits after the s) or when letters are missing.
Decades are the trap that reaches professional writing. "The 1990s" takes nothing. "The '90s" takes an apostrophe at the front, standing in for the omitted 19, exactly the job it does in "'tis" and "'round." "The 1990's" is wrong in every current major style, and "the 90's" manages to be wrong twice. Abbreviations follow the decades rule: "CDs," "URLs," "MPs." You will find "CD's" in mid-century print, because some older house styles allowed it, but the current consensus is no apostrophe.
A five-minute apostrophe audit
Before anything with your name on it leaves the building:
- Search for "'s" and interrogate every hit: what is possessed, or which letters vanished? If neither question has an answer, the apostrophe is unemployed. Delete it.
- Search for "s'" and confirm the noun is genuinely plural before letting it stand. "The students' lounge" needs many students; if there is one student, you want "student's."
- Expand every "it's" and check the fit. Expand every contraction in headings while you're there, where errors hide longest because headings get read least.
- Run the draft through a grammar checker and a spelling checker. Apostrophe errors are pattern problems, and pattern problems are what software does best, precisely because your eye habituates to your own mistakes.
If you want the full sweep, a self-editing checklist folds these searches in with the rest of a proper proofreading pass, so the apostrophes get audited in context rather than in a panic at midnight.
Frequently Asked Questions
Is it "James' book" or "James's book"?
Both are correct depending on your style guide: Chicago prescribes "James's" (and pronounces it "James-iz"), while AP typically prescribes "James'." Pick the style your publisher or workplace follows and apply it to every name ending in s without exception, because exceptions look like mistakes even when they're deliberate.
How do I sign a holiday card from a family?
Pluralize the surname by sound and add no apostrophe: "Merry Christmas from the Garcias," "Love, the Kennedys," "Warmly, the Joneses." Names ending in s, x, z, ch, or sh take "es"; everything else takes "s." The apostrophe stays out of it no matter how bare the name looks, because the card is signed by the whole family, not owned by it.
Do decades ever take apostrophes?
Only in shortened form, and only at the front: "the '90s," where the apostrophe replaces the missing 19. The full form "the 1990s" takes nothing, and "the 1990's" is wrong in every major current style. The same front-of-the-word apostrophe gives us "'tis the season."
Why doesn't possessive "its" have an apostrophe?
Because English settled the convention badly. In earlier centuries, "it's" served for both the possessive and the contraction, and the modern split only hardened in the nineteenth century. The possessive was patterned with "his" and "hers," which never carried apostrophes. The result is one punctuation mark doing double duty in readers' memories, which is why the error survives even in careful writers.
Are there any plurals that legitimately take apostrophes?
A few, all involving letters or symbols that would be unreadable otherwise: "dot your i's" (otherwise "dot your is"), "mind your p's and q's," "the equation has two x's." Note what the exception teaches: the apostrophe appears only where the plain plural would smear into another word, and never on ordinary nouns, numbers, or abbreviations.
The apostrophe's only alibi
Before typing one, ask what it stands for: missing letters, or ownership. If you can answer, the mark is earning its keep, and whether it sits before the s, after it, or at the front of "'90s" follows from the answer. If you can't answer, you're probably making a plural, and plurals have never needed its help. Ask that question of the next apostrophe you type, and it will become automatic within a week.