Have you ever found yourself typing “hence why” and pausing, unsure if it sounds right?
You’re not alone. Many fluent English speakers—including professionals—use this phrase without realizing it’s grammatically redundant.
Yet, it appears everywhere from blogs to academic writing.
So, what’s the real story? Is “hence why” grammatically correct? Let’s dive deep into the logic, history, and practical grammar rules behind this controversial phrase—and learn what to use instead.
Understanding the Redundancy in “Hence Why”
At first glance, “hence why” looks natural. Both words seem to point toward a reason or result. But that’s exactly the issue.
- “Hence” means for this reason or as a result.
- “Why” also means for what reason or because.
When you combine them, you end up saying the same thing twice. That’s called tautology—a redundancy that weakens your sentence.
Example of redundancy:
❌ He was tired, hence why he left early.
Here, both hence and why express cause. The sentence literally says, He was tired, for this reason for what reason he left early. Awkward, right?
Corrected version:
âś… He was tired; hence, he left early.
The sentence is cleaner, logical, and grammatically precise.
The Correct Usage of “Hence” in American English
In modern American English, hence functions as an adverb, not a conjunction. That means it modifies the clause rather than joining two like because or therefore would.
Common Meanings of “Hence”
| Meaning | Example Sentence | Explanation |
|---|---|---|
| For this reason | The storm damaged the bridge; hence, the delay. | Shows cause and effect. |
| From this place | She went hence to Paris. | Archaic use (rare today). |
| From now on / from this time | A year hence, we’ll meet again. | Refers to future time. |
Grammar Tip
When hence starts a clause, it’s usually followed by a comma in formal writing:
Prices have increased; hence, fewer customers are buying.
But in informal writing, the comma is often dropped:
It’s raining, hence the canceled game.
Examples of Proper “Hence” Usage
Let’s see hence in action across different sentence types.
- Cause and Effect: He didn’t water the plants; hence, they died.
- Formal Explanation: Demand exceeded supply; hence the price hike.
- Short Form Without Verb: No rain for months—hence the drought.
- Archaic / Literary: He departed hence never to return.
Notice how hence replaces longer connectors like for that reason or because of that.
Why “Hence Why” Sounds Wrong — But Still Appears Everywhere
If “hence why” is wrong, why do so many people use it? The short answer: habit and rhythm.
Common Reasons It Persists
- Reinforcement: Speakers double up words like hence why for emphasis.
- Blending Speech Patterns: In conversation, we often join hence (formal) with why (colloquial) unconsciously.
- Language Drift: Over time, phrases spread through imitation, not grammar books.
Think of phrases like “reason why” or “return back.” They’re redundant, but people still say them every day. The same process drives “hence why.”
When It Might Pass (But Shouldn’t)
In casual speech, saying “hence why” won’t raise many eyebrows. But in professional or academic writing, it signals poor grammar awareness. Editors and professors consider it sloppy.
So, if clarity and credibility matter, skip “hence why.”
Replacing “Hence Why” With Smarter Alternatives
You can fix “hence why” by choosing one clear connector instead of two. Here’s how.
| Incorrect | Correct | Better Choice | Why It Works |
|---|---|---|---|
| Hence why he left early. | Hence, he left early. | Hence | Removes redundancy. |
| Hence why we missed it. | That’s why we missed it. | That’s why | Fits natural tone. |
| Hence why the confusion. | Therefore, the confusion. | Therefore | Best for formal tone. |
| Hence why it happened. | Thus, it happened. | Thus | Works in academic writing. |
Quick Rewrite Strategy
When tempted to use “hence why,” pause and ask:
👉 Am I expressing a reason or a result?
If yes, pick only one: hence, therefore, thus, or that’s why.
“Hence Why” vs. “That’s Why”: Choosing the Right Conjunction
While hence and that’s why look similar, their tone and usage differ.
| Feature | “Hence” | “That’s Why” |
|---|---|---|
| Tone | Formal / academic | Conversational |
| Grammar Type | Adverb | Clause connector |
| Example | She was late; hence, she missed the start. | She was late, that’s why she missed the start. |
| Best For | Essays, reports, research papers | Everyday conversation, storytelling |
Tip: Use hence in polished writing and that’s why when speaking or blogging casually.
A Historical Look at “Hence Why” and Modern Usage
Hence comes from Middle English hens, meaning from here or from this. It evolved from Old English heonan (“away” or “from this place”).
Historically, English writers used hence to denote movement or origin, like:
Go hence, and trouble me no more!
As centuries passed, it gained its modern causal meaning (for this reason).
So where did “hence why” appear? Linguists trace it to informal British English in the 19th–20th centuries, likely from blending “and that’s why” with “hence.”
Over time, it crept into speech and online writing—proof that even incorrect forms can thrive when they sound natural.
How Language Evolution Impacts Grammar Rules
English isn’t static—it evolves. What’s wrong today might become accepted tomorrow.
Consider these examples:
- “Contact” was once only a noun, not a verb.
- “Hopefully” meant “in a hopeful way,” not “it is to be hoped.”
- “Irregardless” started as an error but appears in major dictionaries today.
That said, “hence why” hasn’t reached that level of acceptance. Major style guides like The Chicago Manual of Style and Merriam-Webster’s Usage Notes still flag it as redundant.
So, while English flexes, you should still write with clarity and precision.
Common Redundant Phrases Like “Hence Why”
Redundancy creeps into everyday English more often than we think. Here are some frequent offenders.
| Redundant Phrase | Correct Form | Why It’s Redundant |
|---|---|---|
| Reason why | Reason | “Why” repeats “reason.” |
| Return back | Return | “Return” already means “go back.” |
| Free gift | Gift | All gifts are free by definition. |
| ATM machine | ATM | “M” in ATM means “machine.” |
| PIN number | PIN | “N” stands for “number.” |
| End result | Result | “Result” implies an end. |
Editing Tip
When revising, look for phrases where two words express the same idea. Cutting one strengthens your writing instantly.
Expert Advice: Using “Therefore” and “Thus” Instead of “Hence Why”
When you want to sound professional, “therefore” and “thus” make excellent alternatives to “hence why.”
Using “Therefore”
- Best in logical or argumentative writing.
- Usually follows a semicolon or starts a new sentence.
Examples:
She studied hard; therefore, she passed the exam.
The data were incomplete; therefore, the results are inconclusive.
Using “Thus”
- Works well in scientific, academic, and formal writing.
- Suggests a natural consequence rather than direct cause.
Examples:
The temperature dropped suddenly; thus, the crops failed.
Thus, it can be concluded that the hypothesis is valid.
Comparison Table
| Word | Use Case | Tone | Example |
|---|---|---|---|
| Hence | Logical consequence | Formal | He was late; hence, he missed the meeting. |
| Therefore | Logical proof or argument | Academic | The data were flawed; therefore, the conclusion is invalid. |
| Thus | Summarizing or concluding | Scientific / Professional | Thus, the experiment confirmed our theory. |
Practical Tips for Writers and Students
Want to avoid redundancy like “hence why” in your writing? Follow these quick tips.
1. Rely on Grammar Tools (But Don’t Trust Them Blindly)
Tools like Grammarly or ProWritingAid catch redundancy but sometimes miss nuance. Always double-check context.
2. Read Aloud Before Submitting
If a phrase sounds repetitive or awkward when spoken, it likely is.
3. Use Style Guides
Refer to AP, Chicago, or Oxford guides for consistent usage.
4. Replace Filler Words
Cut out really, very, actually, and similar words that don’t add meaning.
5. Keep It Simple
Clarity beats complexity every time. Write for humans, not for grammar police.
Case Study: How One Writer Improved Clarity
Before Editing:
He didn’t prepare, hence why the project failed, which is unfortunate because he’s usually diligent.
After Editing:
He didn’t prepare; hence, the project failed. He’s usually diligent, so it was surprising.
Result:
The edited version removes redundancy, shortens the sentence, and improves readability. Readers follow the logic smoothly without tripping over extra words.
Quotes From Grammar Experts
“Good writing is lean writing. Every unnecessary word weakens your meaning.”
— William Zinsser, On Writing Well
“Redundancy is the enemy of clarity.”
— Bryan A. Garner, Garner’s Modern English Usage
Both authors emphasize the same point: concise writing reflects precise thinking.
FAQs About “Hence Why”
Is “Hence Why” Grammatically Correct?
No. It’s considered redundant because both hence and why indicate cause or reason. Use hence or that’s why, not both.
Can I Use “Hence Why” in Speech?
In casual conversation, yes—but avoid it in professional or academic writing. It sounds informal and grammatically weak.
What’s a Better Alternative to “Hence Why”?
Try “hence,” “that’s why,” “therefore,” or “thus” depending on tone and context.
Is “Hence” Outdated?
Not at all. It’s formal, but still common in business, academic, and technical writing.
How Can I Remember to Avoid “Hence Why”?
Simple rule: if your sentence already explains a reason, drop why after hence.
Conclusion
So, is “hence why” grammatically correct? No—it’s redundant and unnecessary. Both words mean for this reason, so using them together repeats the same idea.
Language evolves, and casual speech often bends the rules, but strong writing depends on clarity and precision. If you want your words to sound polished and professional, choose one connector—hence, therefore, thus, or that’s why.
In the end, mastering small details like this sets good writers apart from average ones. After all, clarity is the hallmark of great communication.

Hi! I’m Sami, a 28-year-old content writer with a love for words and storytelling. Writing has always been my way of expressing ideas, sharing knowledge, and connecting with people. I enjoy creating engaging and well-researched content—whether it’s blogs, articles, or social media posts—that not only informs but also inspires readers. My goal is to turn complex ideas into clear, creative, and meaningful pieces of writing that leave a lasting impact.


