That's vs thats: The Apostrophe Mistake Most Writers Miss — Explained 2026

That's vs thats is one of those grammar slips that hides in plain sight. You spot it in emails, captions, and even polished articles, and one missing apostrophe makes an otherwise sharp sentence look rushed. The tricky part is how familiar the wrong form feels, because we scroll past thats constantly on social media. See also study routine. Comparable cases in home printing.

This guide clears it up for good. Related context in spelling rules.

By the end you'll know exactly when to write that's, when thats is acceptable, and how a quick proofreading habit catches the error before anyone else does. More background in grammar rules. Wider detail in writing tips.

Understanding the Basics: That’s vs Thats

The difference between that’s and thats comes down to one thing:
the apostrophe.

• That’s is a contraction
• Thats is not a standard English word in normal writing

That apostrophe isn’t decoration. It carries meaning.

Quick comparison

If the apostrophe disappears, the grammar collapses with it.

What That’s Really Means in Grammar

That’s is a contraction.
A contraction shortens two words into one.

In English, that’s can stand for only two phrases:

• that is
• that has

Nothing else.

If neither phrase fits your sentence, that’s does not belong there.

When That’s Means “That Is”

This is the most common use of that’s.

How it works

If you can replace that’s with that is and the sentence still makes sense, the usage is correct.

Examples

• That’s my phone.
  → That is my phone.
• That’s the reason we left early.
  → That is the reason we left early.
• That’s exactly what I meant.
  → That is exactly what I meant.

The meaning stays intact. The sentence flows naturally. That’s how you know it’s right.

Spoken vs written English

In speech, that’s feels natural and effortless.
In writing, it keeps the tone conversational but still correct.

When That’s Means “That Has”

This usage confuses many writers because it hides quietly in sentences.

Here, that’s replaces that has, usually in the present perfect tense.

Structure

that’s + past participle

Examples

• That’s been a long day.
  → That has been a long day.
• That’s caused a lot of confusion.
  → That has caused a lot of confusion.
• That’s changed my opinion.
  → That has changed my opinion.

If you replace that’s with that has and the sentence still works, the grammar is correct.

Why Thats Is Usually Wrong

In standard English, thats without an apostrophe is almost always incorrect.

Why?

Because English requires apostrophes to show missing letters in contractions.

When you write thats, you’re removing:

• the apostrophe
• the grammatical signal
• the meaning

The sentence loses clarity and correctness.

Why autocorrect doesn’t always fix it

Autocorrect often ignores thats because:

• It appears frequently in casual writing
• It’s not always flagged as a spelling error
• Context matters, and machines struggle with that

That means the responsibility falls on you.

The Only Real Case Where Thats Is Correct

There is one legitimate exception.

Proper nouns and brand names

Some brand names ignore grammar rules intentionally. When Thats appears as part of a registered name, it’s correct within that name only.

Example:

• Honda That’s (a model name)

This does not make thats correct in normal sentences.

Brand spelling follows branding rules, not grammar rules.

Common Misconceptions That Cause the Thats Mistake

Most people don’t make this error because they’re careless. They make it because of habits.

Misconception one: Apostrophes are optional

They are not. Apostrophes carry meaning.

Misconception two: Texting rules apply everywhere

Casual texting habits bleed into professional writing.

Misconception three: Possession confusion

Some writers mistakenly think that’s shows possession. It does not.

That’s never shows ownership.

That’s vs That Is vs That Has: How to Choose Correctly

Here’s a simple decision method you can use every time.

The replacement test

Ask yourself:

• Can I replace it with that is?
• Can I replace it with that has?

If the answer is yes to either, that’s is correct.

If the answer is no to both, rewrite the sentence.

Examples

• That’s finished already.
  → That has finished already ✔
• Thats my bag.
  → That is my bag ✔ → needs apostrophe
• Thats ideas are outdated.
  → No correct replacement ✘ → rewrite sentence

Real-World Examples of That’s in Everyday Writing

Casual conversation

• That’s amazing news.
• That’s not what I expected.
• That’s been bothering me all day.

Emails and professional writing

• That’s attached for your review.
• That’s been approved by management.
• That’s the final version of the report.

Academic and formal contexts

In very formal writing, contractions may be avoided.
Still, that’s remains grammatically correct.

Why Using That’s Correctly Matters

Small grammar errors send big signals.

Correct usage shows:

• attention to detail
• language awareness
• professionalism

Incorrect usage suggests:

• rushed writing
• weak editing
• poor command of basics

As writer David Foster Wallace once said:

“Good writing is not just about ideas, it’s about respect for the reader.”

Grammar earns that respect.

Quick Checklist to Avoid the Thats Error

Before you hit publish or send, ask:

• Did I mean that is or that has?
• Did I include the apostrophe?
• Does the sentence still make sense when expanded?

If yes, you’re safe.

How I Finally Trained My Eye to Catch thats

I used to skim past thats without a flicker, until an editor flagged three in one draft. What fixed it was not memorizing rules but changing how I read. Now I proofread backward, sentence by sentence from the last line up, because my brain stops auto-correcting and the missing apostrophe finally jumps out. I keep reading list bookmarked.

My second trick is reading aloud. When I hit thats, I ask whether the sentence needs that is or that has, and the wrong form suddenly sounds clipped. I also keep a short list of my repeat offenders, much like tracking probability language patterns, and run a find-and-replace for thats before I publish anything. For longer projects, a study routine built around spaced review keeps the rule fresh. It takes two minutes and saves a lot of embarrassment. I covered that in laptop deals. I tested it, see what skills can.

Frequently Asked Questions About That’s vs Thats

What is the difference between that’s and thats?

That’s is a contraction for that is or that has. Thats is usually incorrect.

Is thats ever correct in English?

Only in proper names or brand titles. Not in normal sentences.

How do I know if that’s means that is or that has?

Replace it with that is or that has. Whichever works reveals the meaning.

Why do people confuse that’s with thats?

Texting habits and missing apostrophes cause the confusion.

How can I permanently stop writing “thats”?

Use the replacement test every time you write it.

Final Summary

Here’s the rule that ends the confusion:

If you mean “that is” or “that has,” use that’s.
If not, rewrite the sentence.

There are no shortcuts.
There are no hidden meanings.
Just one apostrophe doing important work.

Once you respect it, your writing instantly looks sharper and more professional.