When Should You Use Their? | The Rule Most Writers Miss

“Their” looks harmless until it lands next to “there” and “they’re.” Then the whole sentence can wobble. If you pause on that trio, you’re not alone. This is one of the most common mix-ups in English, and it shows up in school papers, work emails, captions, texts, and polished blog posts.

The good news is that “their” follows one clean rule. It shows possession. In plain terms, it points to something that belongs to them. Once that clicks, most mistakes fall away.

This article gives you the rule, the fast checks that catch errors, and the sentence patterns where “their” earns its place. You’ll also see where writers trip up, why singular “their” is standard English, and how to fix shaky lines without overthinking them.

What “Their” Means In Plain English

“Their” is a possessive word. It sits before a noun and tells you who owns, uses, carries, wears, chose, or received that noun. Think of it as the same kind of word as “my,” “your,” and “our.”

If the sentence can answer the question “belongs to whom?” and the answer is “them,” “their” is often the right pick. That’s the whole engine behind it.

• Their coats were soaked after the storm.
• We packed their lunch before school.
• The players lifted their trophy after the match.
• The neighbors painted their fence last weekend.

In each case, “their” points to a noun: coats, lunch, trophy, fence. That’s a pattern worth locking in. If no noun follows, you may need another word, such as “theirs,” which stands alone: “The coats are theirs.”

When Should You Use Their? In Real Sentences

Use “their” when you’re naming something tied to people or to a person whose gender you’re not stating. It works in everyday writing, formal writing, and edited publishing. Standard dictionaries define it as the possessive form linked to “they,” and writing handbooks place it in the possessive pronoun family. You can confirm that in Merriam-Webster’s entry for “their” and Purdue OWL’s section on pronoun case.

That broad rule becomes easier when you spot the sentence shapes where “their” shows up again and again.

Before A Concrete Thing

This is the most common pattern. A group of people owns or uses a thing.

• The students opened their laptops.
• The guests left their shoes by the door.
• The twins forgot their keys.

Before An Abstract Noun

“Their” also works with words you can’t hold in your hand. People can have goals, views, fears, plans, and opinions.

• The board changed their decision.
• Writers shape their style over time.
• The kids shared their ideas with the class.

For One Person When Gender Is Unknown Or Not Named

Singular “their” is normal in modern English. You’ll hear it in speech and see it in edited text: “Someone left their phone on the table.” That sentence sounds natural because the person is unknown, and “their” keeps the line smooth without forcing “his or her.” Purdue OWL also notes this current use in its page on singular they.

That use helps when the subject is a word like someone, anyone, each person, no one, or a job title tied to an unknown person.

• If anyone calls, take their name.
• Every driver should check their mirrors.
• A reader sent their feedback this morning.

Fast Checks That Stop Most Mistakes

You don’t need to diagram a sentence to get this right. A few short checks catch the slip almost every time.

Check The Word After It

If a noun follows, “their” may fit. “Their bag,” “their turn,” “their answer,” “their team.” If the next word is a verb, pause. “Their going” is wrong if you mean “they’re going.”

Swap In “Our”

Try replacing “their” with “our.” If the sentence still works, you’re on solid ground.

• Their house is on the corner. → Our house is on the corner.
• Their running late. → Our running late. That falls apart, so “their” is wrong there.

Ask Whether Ownership Is Part Of The Sentence

Does the sentence show belonging? If yes, “their” is a strong candidate. If the sentence points to a place, use “there.” If it expands to “they are,” use “they’re.”

Word	What It Does	Example
Their	Shows possession before a noun	Their tickets were in my bag.
There	Points to a place or position	Your seat is over there.
They’re	Short form of “they are”	They’re ready to leave.
Theirs	Shows possession without a noun after it	The blue car is theirs.
There’s	Short form of “there is”	There’s a note on the desk.
Them	Object form, not possession	I met them after lunch.
They	Subject form, not possession	They missed the train.
Themselves	Reflexive form	They taught themselves guitar.

Where Writers Usually Slip

Most errors with “their” come from sound, not meaning. The three words sound alike, so the ear won’t save you. The sentence has to do that job.

Mixing Up Possession And Contraction

The classic error is writing “their” when the sentence needs “they’re.” Read the line out as “they are.” If it works, the apostrophe version wins.

• Wrong: Their going to miss the bus.
• Right: They’re going to miss the bus.

Using “Their” Without A Noun

“Their” usually needs a noun after it. If the noun is missing, you may need “theirs.”

• Wrong: The red seats are their.
• Right: The red seats are theirs.

Forcing Singular And Plural To Clash

Agreement still matters. If your subject is plural, “their” can fit with ease. If your subject is singular and specific, match the sentence with care. Yet when the person is unknown or not named, singular “their” is accepted and common.

If you want a clean explainer on the full trio, Merriam-Webster’s page on there, they’re, and their is a handy reference.

How To Tell If “Their” Belongs In Your Sentence

When you edit your own work, run a short sequence instead of staring at the word and hoping the answer appears.

1. Find the noun linked to the word.
2. Ask who owns, uses, or holds that noun.
3. If the answer is “they” or “them,” test “their.”
4. If no noun follows, test “theirs.”
5. If the line expands to “they are,” switch to “they’re.”
6. If the line points to a place, switch to “there.”

That sequence works in school essays, business copy, blog posts, and social posts. It’s short enough to become a habit, and habits beat memory tricks.

Sentence	Best Word	Why It Fits
The kids forgot ___ backpacks.	Their	“Backpacks” is a noun owned by them.
___ waiting by the car.	They’re	The sentence means “they are waiting.”
Put the boxes over ___.	There	The sentence names a place.
The choice was ___, not ours.	Theirs	Possession stands alone without a noun.
Someone left ___ scarf on the chair.	Their	Singular “their” works with an unknown person.

Using “Their” With Confidence In Daily Writing

The cleanest writing often comes from plain choices. “Their” is one of them. You use it when a person or group has something, chose something, made something, lost something, or is tied to something named right after the word. That’s it.

When you feel stuck, stop listening to the sound and start reading for function. What job is the word doing? Possession, place, or contraction? Once you answer that, the right form tends to show itself fast.

A final editing trick helps more than most people expect: read the sentence once from the noun backward. “Their report,” “their office,” “their reply,” “their dog.” That backward glance makes the ownership link stand out, and it can catch errors your eye skipped on the first pass.

If you build that habit, “their” stops feeling slippery. It becomes one of the easier choices on the page.