Their or They’re: Which Is Correct?
If you have ever typed they’re, deleted it, retyped their, deleted that too, and finally rewritten the whole sentence to dodge the problem — welcome to the club. “Their or they’re” is one of the most searched grammar questions in English, and it is also one of the least forgiving: careful readers notice the mistake instantly, and no spellchecker will ever save you, because both spellings are perfectly good words.
The entire confusion fits in one sentence. Their shows possession: “their house,” “their decision.” They’re is a contraction of “they are“: “they’re late” means “they are late.” The reason the error never dies is that the two words sound exactly the same — Merriam-Webster opens its usage note with exactly this point: “There, they’re, and their: they sound the same but have different meanings and keeping them straight can be very tricky.”
Why Your Ear Can’t Help You
Most spelling errors are accidents of typing. This one is an accident of hearing. In standard British and American accents, their, they’re — and there — are pronounced identically. Oxford Learner’s gives their as /ðeə(r)/ in British English and /ðer/ in American English, while the Britannica/Merriam-Webster audio dictionary gives they’re as /ðɚ/ in American English: the same sound wearing different spellings. Your brain stores the sound; your hand has to pick the spelling from meaning alone.
That is also why autocorrect is useless here. A spellchecker only asks “is this a word?” — and both answers are yes. Grammar checkers catch some cases but stumble on exactly the sentences where you are most likely to slip: long, fast-typed messages where the context is thin. The only reliable fix is knowing what each spelling is for, so the choice becomes a grammar decision instead of a guess.
“Their”: The Possessive
Their is a possessive determiner. Collins defines it as “of, belonging to, or associated in some way with them,” and Oxford Learner’s calls it simply “the possessive form of they.” It sits in front of a noun and answers the question whose?
- The students forgot their textbooks. (Whose textbooks? Theirs.)
- Their decision surprised everyone.
- The trees are losing their leaves. (Merriam-Webster’s own example — yes, their works for things too, not just people.)
- Everyone should bring their own lunch. (Collins’s example — the modern singular-they use.)
Two properties nail it down. First, their never contains a verb — it is a determiner, a word whose job is to introduce a noun phrase. Second, it never takes an apostrophe. This trips up people who learned that possession is spelled with ‘s: their’s is always wrong, just as her’s, our’s, and your’s are. Possessive determiners — my, your, his, her, its, our, their — do their possessing without any punctuation at all.
One modern note worth having: their is also the standard gender-neutral singular possessive. “Each student has been given their own email address” is, as Oxford Learner’s usage note puts it, more common in everyday English than “his or her own email address.” If you were taught that their must always be plural, update the rule — the dictionaries have.
“They’re”: The Contraction
They’re does exactly one job: it stands in for they are. Cambridge lists it as “short form of they are,” and the apostrophe is doing real grammatical work — it marks the spot where the letter a was dropped. Cambridge’s own apostrophe guide puts it plainly: “in contracted forms, the apostrophe shows where one or more letters has been left out… they’re means they are.” Cambridge’s entry for they’re lists the same definition with examples like “They’re going to move house soon.”
- They’re going to be late. (= They are going to be late.)
- I think they’re ready. (= …they are ready.)
- They’re the cutest puppies ever. (One of Merriam-Webster’s examples — contractions work for non-living things too.)
- She said they’re planning a camping trip. (Cambridge’s example sentence.)
Notice the pattern: every correct they’re can be unfolded back into they are without breaking the sentence. They’re does the work of a subject plus the verb be — sometimes as the main verb (“they’re happy”), sometimes as an auxiliary (“they’re leaving”). If there is no are-shaped hole in your sentence, they’re cannot go there.
A register note: contractions are informal. Cambridge’s apostrophe guide reminds writers that contracted forms “are not suitable for very formal writing, where it is better to write the words in full.” In a dissertation, a legal brief, or a formal report, write they are. In emails, articles, and everything conversational, they’re is perfectly at home.
The Two-Second Test
When in doubt, expand. Replace the word with they are and read the sentence aloud:
- “Their going to win” → “They are going to win” — makes sense, so the apostrophe belongs: “They’re going to win.”
- “They’re house is big” → “They are house is big” — nonsense, so no apostrophe: “Their house is big.”
- “I like their new album” → “I like they are new album” — nonsense: their.
- “Their the best team in the league” → “They are the best team in the league” — works: they’re.
The test never fails because it is not a trick — it is the definition. They’re literally is “they are” with two letters folded into an apostrophe. If “they are” doesn’t fit the slot, neither does they’re.
Correct vs. Incorrect
| Correct | Incorrect |
|---|---|
| Their flight was delayed. | They’re flight was delayed. |
| They’re already here. | Their already here. |
| The kids left their shoes by the door. | The kids left they’re shoes by the door. |
| I hear they’re hiring. | I hear their hiring. |
| It wasn’t their fault. | It wasn’t they’re fault. |
| They’re bringing their dog. | Their bringing they’re dog. |
Common Mistakes
1. Writing “their’s”
Possession makes people reach for the apostrophe — that is the ‘s rule misfiring. But their belongs to a closed family of possessive determiners (my, your, his, her, its, our, their) that never take apostrophes. “A friend of theirs” is the form with the extra s — and even there, no apostrophe.
2. Dragging “there” into it
The full trio is there / their / they’re, and there is the third homophone: the place word (“put it there,” “there are five apples”). Merriam-Webster’s memory hook still works — “there has the word here in it, which can help remind us that this particular word is often about location.” Merriam-Webster’s usage note covers all three together. If the sentence is about a place or existence, you want there — neither of today’s two spellings.
3. Using “they’re” where formality matters
Nothing is grammatically wrong with they’re in an email. In a thesis or a contract, though, contractions read as careless. Cambridge’s style advice is the rule of thumb: formal writing spells out “they are.”
4. Assuming it doesn’t matter because “everyone understood”
Often true in a text message, rarely true where it counts. “Their ready” in a job application reads as a basic literacy slip to a hiring manager — unfairly, maybe, but predictably. And sometimes the wrong choice genuinely changes the meaning: “they’re house” is not just wrong, it is unparseable.
Pronunciation: UK vs. US
The dictionary forms, side by side:
- Their: UK /ðeə(r)/, US /ðer/ (Oxford Learner’s Dictionaries)
- They’re: US /ðɚ/ (Britannica / Merriam-Webster audio dictionary)
In practice, standard accents pronounce the whole trio — there, their, they’re — the same way, which is precisely why this error survives spellcheck. The spelling carries the meaning; the sound carries none of it. When you proofread, read for the job each word is doing, not for how it sounds in your head.
FAQs
Can “their” and “they’re” appear in the same sentence?
Yes — and the sentence is a perfect self-test: “They’re bringing their dog.” Expand the first (“they are bringing…”) and it works; expand the second (“they are dog”) and it collapses. Two words, two jobs, one sentence.
Is “there” part of this confusion too?
Almost always. The classic trio is there (place/existence), their (possession), they’re (they are). This article focuses on the pair the question asks about, but if you mix up all three, learn the trio together — Merriam-Webster’s “there has here in it” hook is the fastest way to pin down the third member.
What about “theirs”?
Theirs is the standalone possessive pronoun: “The house is theirs.” It replaces a noun phrase entirely, where their introduces one (“their house”). Never write it with an apostrophe.
Why doesn’t my spellchecker catch this?
Because both spellings are legitimate dictionary words. A spellchecker verifies spelling, not meaning — it cannot know whether you meant possession or “they are.” Only the grammar of your sentence knows, which is why the expand-to-“they are” test beats any software.
Can I just write “they are” every time and skip the contraction?
You can, and in formal writing you should. Elsewhere it reads as stiff — “They are going to love it” in a chat message sounds like a press release. The contraction exists for natural rhythm; learn the rule once and use it freely.
The Takeaway
Their = possession (“their house”) — Oxford Learner’s “the possessive form of they.” They’re = “they are” — Cambridge’s “short form of they are,” the apostrophe marking the missing a. When in doubt, expand the contraction: if “they are” fits, use the apostrophe; if it doesn’t, you want their. The two words sound identical — the spelling is where the meaning lives.
