Have you ever wondered whether the correct spelling is their or thier? You’re not alone. This is one of the most common English spelling mistakes because many people accidentally reverse the letters “e” and “i.” While both spellings may look familiar, only one is correct in standard English.
The correct spelling is their. It is a possessive determiner that shows ownership or belonging to two or more people, animals, or things. It is commonly used in everyday conversations, business writing, academic work, and professional communication.
The spelling thier is incorrect. It is a common misspelling caused by reversing the order of the letters “e” and “i.” Standard English dictionaries recognize only their as the correct spelling.
In this guide, you’ll learn the correct spelling, meaning, pronunciation, grammar rules, US vs. UK usage, examples, common mistakes, memory tricks, and frequently asked questions about their or thier.
Quick Answer
| Spelling | Correct? |
|---|---|
| ✅ Their | Correct |
| ❌ Thier | Incorrect |
Their means belonging to them.
Examples
- Their house is beautiful.
- The students finished their homework.
- The children packed their bags.
What Does “Their” Mean?
Their is a possessive determiner.
It shows that something belongs to two or more people, animals, or things. It can also be used with the singular they in modern English.
Examples
- Their car is parked outside.
- The team celebrated their victory.
- Someone left their phone on the table.
- The birds built their nests.
Why Is “Thier” Incorrect?
The spelling thier is incorrect because the letters “e” and “i” are in the wrong order.
Correct:
Their
Incorrect:
❌ Thier
No standard English dictionary accepts thier as the correct spelling.
Grammar Role of Their
Their functions as a possessive determiner.
Common Expressions
- Their house
- Their family
- Their children
- Their opinion
- Their decision
- Their responsibility
Examples
- Their teacher praised them.
- Their ideas were creative.
- The players celebrated their success.
Their in American English
American English uses their.
Examples
- Their house is on the corner.
- The students submitted their assignments.
- The company announced their plans.
- They brought their luggage.
Their in British English
British English also uses their.
Examples
- Their garden is beautiful.
- The children packed their bags.
- The team celebrated their victory.
- They completed their work.
There is no spelling difference between American and British English.
Their vs Thier
| Feature | Their | Thier |
|---|---|---|
| Correct spelling | ✅ Yes | ❌ No |
| Dictionary word | Yes | No |
| Meaning | Belonging to them | No meaning |
| Part of speech | Possessive determiner | Incorrect spelling |
| American English | Yes | No |
| British English | Yes | No |
Pronunciation
Their
UK IPA: /ðeə(r)/
US IPA: /ðer/
Pronunciation:
THAIR
Although it is pronounced like there and they’re, the correct spelling for possession is their.
Common Uses of “Their”
Family
- Their parents
- Their children
School
- Their homework
- Their teacher
Business
- Their company
- Their project
Everyday Life
- Their home
- Their car
Their vs Similar Words
| Word | Meaning |
|---|---|
| Their | Belonging to them |
| There | Refers to a place or introduces a sentence |
| They’re | Contraction of they are |
| Theirs | Possessive pronoun |
Common Mistakes
Incorrect
❌ Thier house is beautiful.
Correct
✅ Their house is beautiful.
Incorrect
❌ The students forgot thier books.
Correct
✅ The students forgot their books.
Incorrect
❌ They love thier dog.
Correct
✅ They love their dog.
Incorrect
❌ Everyone packed thier bags.
Correct
✅ Everyone packed their bags.
Real-Life Examples
School
- Students submitted their homework.
- The teacher returned their tests.
Workplace
- Employees attended their meeting.
- The company announced their new policy.
Everyday Life
- They washed their car.
- The family decorated their home.
Sports
- The players celebrated their championship.
- The team improved their performance.
American English Example Sentences
- Their house is beautiful.
- The students finished their homework.
- They packed their bags.
- The company changed their policy.
- Their children are very polite.
- They love their dog.
- The players celebrated their victory.
- Their friends arrived early.
- They completed their project.
- Their ideas impressed everyone.
British English Example Sentences
- Their garden is lovely.
- The pupils finished their work.
- They packed their suitcases.
- The company revised their policy.
- Their neighbours were friendly.
- They enjoyed their holiday.
- The team celebrated their success.
- Their family visited Scotland.
- They brought their umbrellas.
- Their efforts were appreciated.
Easy Memory Tricks
Remember “Heir”
The word their contains heir:
T + heir = Their
This can help you remember the correct order of the letters.
Think of Ownership
If something belongs to them, always use their.
Example:
- Their house
- Their books
- Their ideas
Practice
Write it three times:
Their
Their
Their
Frequently Asked Questions
Is their or thier correct?
Their is the correct spelling.
Is thier a real word?
No. It is a common spelling mistake.
What does their mean?
It means belonging to them.
Is their a possessive word?
Yes. It is a possessive determiner.
How do you spell their?
T-H-E-I-R
Is the spelling different in British and American English?
No. Both use their.
How do you pronounce their?
THAIR
People Also Ask
Why do people spell their as thier?
Because they accidentally reverse the letters “e” and “i.” The correct spelling is their.
Is their used in formal writing?
Yes. It is widely used in academic, business, legal, and everyday English.
What’s the easiest way to remember their?
Think:
Their = Belonging to them
Or remember the pattern:
T + heir = Their
What’s the difference between their, there, and they’re?
- Their = shows ownership (Their car)
- There = refers to a place (The book is over there)
- They’re = contraction of they are (They’re happy)
Conclusion
If you’re choosing between their and thier, the correct spelling is their. Thier is a common spelling mistake caused by reversing the letters “e” and “i.”
Their is a possessive determiner that means belonging to them. It is the standard spelling in both American and British English. A simple way to remember it is to think of “their house” or “their books,” and remember that their always spells T-H-E-I-R.
