Many people type thier or their and stop to wonder which spelling is correct. This mistake appears everywhere, from student assignments to social media posts and even professional emails. Since both spellings look similar, writers often mix the letters by accident.
People search this keyword because they want to confirm the correct spelling quickly. A small typing error can make writing look careless, even when the idea is clear.
The confusion usually happens because people switch the letters i and e, especially when typing fast.
This guide clears the confusion in simple words. You will learn the correct spelling, why mistakes happen, and how to avoid them.
With easy explanations and examples, you can improve your writing and feel confident using the correct word every time. Let’s break the rule clearly.
Quick Answer
Their is correct.
Thier is a spelling mistake.
Examples
- This is their house.
- The students forgot their books.
Always use their when showing possession for more than one person.
The Origin of Thier or Their
The word their comes from Old Norse þeirra, meaning belonging to them. It entered English during Viking influence in Britain.
The spelling developed over time but kept the letter order e before i in this word. The incorrect form thier appeared later due to typing mistakes and confusion with other English spelling patterns.
The difference exists simply because people often swap letters while typing quickly.
British English vs American English Spelling
Both British and American English use the same spelling.
| Usage Type | British English | American English |
| Possessive pronoun | Their | Their |
| Incorrect spelling | Thier | Thier |
| Formal writing | Their | Their |
| Informal writing | Their | Their |
| There is no regional difference. |
Which Spelling Should You Use?
Always use their, regardless of audience.
Audience Advice
- US audience: Use their.
- UK/Commonwealth: Use their.
- Global writing: Use their.
The spelling never changes.
Common Mistakes with Thier or Their
Many writers switch letters accidentally.
| Mistake | Correct Form |
| Thier house is big | Their house is big |
| I met thier parents | I met their parents |
| Thier car is outside | Their car is outside |
| Thier friends arrived | Their friends arrived |
| Slow typing helps avoid mistakes. |
Thier or Their in Everyday Examples
Emails
“Please collect their documents.”
News Headlines
“The players celebrated their victory.”
Social Media
“They shared their travel photos.”
Formal Writing
“The company announced their results.”
The correct spelling appears in all communication.
Thier or Their – Google Trends & Usage Data
Search interest increases during:
- School writing assignments
- Job application writing
- Social media posting
- Grammar lessons
Popular Regions
- United States
- United Kingdom
- Canada
- India and Australia
Most searches happen when people double-check spelling.
Keyword Comparison Table
| Variation | Usage Context |
| Their | Correct possessive pronoun |
| Thier | Incorrect spelling |
| Their house | Correct usage |
| Their team | Correct usage |
| Their decision | Correct usage |
FAQs
1. Is thier ever correct?
No, it is always incorrect.
2. What does their mean?
It shows possession for them.
3. Why do people write thier?
Because they swap letters while typing.
4. How can I remember correct spelling?
Remember “i” comes after “e” in their.
5. Is spelling different worldwide?
No, it stays the same everywhere.
6. Is their singular or plural?
Usually plural but also used for singular gender-neutral use.
7. Can spell check fix thier?
Yes, most tools correct it.
Conclusion
Understanding thier or their is simple once you know the rule. Their is always correct, while thier is only a common typing mistake.
The confusion happens because English spelling rules are sometimes tricky, and people type quickly without checking letter order.
Using correct spelling improves communication in emails, schoolwork, and professional writing.
Readers may understand your message even with mistakes, but correct spelling makes writing look more polished and trustworthy.
A good habit is to slow down and double-check words that often cause confusion. Spell-check tools can help, but personal awareness is even better.
Now you know the correct form.
Next time you write, you can confidently use their without hesitation and avoid one of the most common spelling mistakes in English writing.
