Confused between their and thier? Discover the correct spelling, simple grammar tips, and easy examples to avoid this common error.
Have you ever typed their and wondered if it should be thier instead? You’re not alone. This is one of the most common English spelling mistakes because the letters i and e are easy to switch by accident. Many students, writers, and English learners search for their or thier to find out which spelling is correct.
The answer is simple: their is the correct English word, while thier is a spelling mistake. Although thier appears in text messages, online comments, and typing errors, it is not accepted in standard English dictionaries.
Knowing the correct spelling helps you write better emails, school assignments, business documents, and social media posts. It also makes your writing look more professional and easier to understand. In this guide, you’ll learn the meaning of their, why people confuse it with thier, its history, common mistakes, real-life examples, and helpful tips to remember the correct spelling every time.
Their or Thier – Quick Answer
Their is the correct spelling.
Thier is a misspelling and should not be used in standard English.
Their is a possessive determiner that shows ownership.
Simple Examples
- The students forgot their books.
- Sarah and Tom parked their car outside.
- The children enjoyed their vacation.
All of these sentences are correct.
The Origin of Their or Thier
The word their comes from Old Norse, where þeirra meant belonging to them.
Over time, English adopted their as the standard possessive form for they.
The spelling thier did not develop as an accepted English word. It usually happens because people accidentally reverse the letters i and e while typing or writing.
Today, dictionaries recognize only their as correct.
British English vs American English Spelling
Unlike words such as color/colour or traveled/travelled, their has no American or British spelling variation.
Both countries use exactly the same spelling.
| Version | Spelling | Region | Example Sentence |
|---|---|---|---|
| American English | Their | United States | The students finished their homework. |
| British English | Their | United Kingdom | The players celebrated their victory. |
| Australian English | Their | Australia | They cleaned their house. |
| Canadian English | Their | Canada | The children wore their coats. |
Easy Rule
No matter where you write English, always use their.
Which Spelling Should You Use?
The answer is simple because there is only one correct spelling.
For a US Audience
Always write their.
For a UK/Commonwealth Audience
Always write their.
For Global/SEO Audience
Use their in every situation.
Never use thier, as it is considered a spelling error and may reduce the credibility of your writing.
Common Mistakes with Their or Thier
Many writers accidentally type thier because they switch the order of the letters.
| Incorrect | Correct |
|---|---|
| Thier house is beautiful. | Their house is beautiful. |
| I like thier new car. | I like their new car. |
| Thier teacher is friendly. | Their teacher is friendly. |
| We visited thier office. | We visited their office. |
| The kids forgot thier bags. | The kids forgot their bags. |
Memory Tip
Remember this phrase:
“Heir” is inside “their.”
If someone is an heir, something belongs to them. Likewise, their shows ownership.
Their or Thier in Everyday Examples
Emails
“Please bring their reports to tomorrow’s meeting.”
News Headlines
“Students Receive Their Exam Results”
Social Media
“They finally reached their dream destination!”
Formal Writing
“The participants submitted their applications before the deadline.”
Their or Thier – Google Trends & Usage
Many people search for their or thier because spell-checkers often highlight thier as incorrect.
Students commonly search for this spelling question while doing homework or writing essays. Professionals also check the spelling when preparing emails, reports, or presentations.
Educational websites, grammar blogs, and dictionaries consistently explain that their is the only correct spelling. Searches for thier mainly come from people trying to correct a typing mistake rather than looking for a different word.
Comparison Table
| Feature | Their | Thier |
|---|---|---|
| Correct Spelling | ✅ Yes | ❌ No |
| Dictionary Word | Yes | No |
| Meaning | Shows ownership | None |
| Used in American English | Yes | No |
| Used in British English | Yes | No |
| Formal Writing | Yes | No |
| SEO Friendly | Yes | No |
Frequently Asked Questions
Is their or thier correct?
Their is correct. Thier is a spelling mistake.
Is thier a real English word?
No. Standard English dictionaries do not recognize thier.
Why do people write thier?
It is usually a typing error caused by reversing the letters i and e.
Is their used in American and British English?
Yes. Both American and British English use the spelling their.
How can I remember the correct spelling?
Remember that “heir” appears inside their, helping you connect it with ownership.
Can I use thier in formal writing?
No. Always replace thier with their.
Is their different from there and they’re?
Yes.
- Their = shows ownership.
- There = refers to a place.
- They’re = short for they are.
Conclusion
Choosing between their or thier is one of the easiest English spelling questions once you know the rule. Their is the only correct spelling and is used to show that something belongs to people. Thier is simply a common typing mistake and should never appear in formal or professional writing.
Unlike many English words that have American and British spelling differences, their is spelled the same everywhere. Whether you’re writing an email, school assignment, article, or social media post, always use their. Spell-check tools will usually catch thier, but learning the correct spelling yourself helps you write faster and with more confidence.
By remembering the simple ownership rule and practicing with real examples, you’ll avoid this common mistake and improve the accuracy of your English writing every time.
