Choosing between most importantly and most important can be confusing because both expressions are correct, but they serve different grammatical purposes. The difference becomes easier to understand when you look at how each phrase works in a sentence.
Most important is an adjective phrase that describes something as having the greatest importance or value. For example, you might say, “Your health is the most important thing in life.” On the other hand, most importantly is an adverb phrase used to emphasize a key point or introduce the most significant piece of information.
For instance, “Most importantly, always tell the truth.” Although the two expressions are closely related, you cannot always use them interchangeably. In this guide, you’ll learn the difference between most importantly and most important, understand their grammar rules, and explore simple examples for everyday conversations, academic assignments, and professional writing.
What Does “Most Important” Mean?
Most important is a superlative adjective phrase. It describes something that has the greatest importance among several things.
The adjective important means having great value, significance, or influence. Adding most creates the superlative form:
important → more important → most important
For example:
Health is the most important thing in life.
Here, most important describes “thing.” The sentence tells us that health has the highest level of importance compared with other things.
Examples of “Most Important”
- This is the most important decision we need to make.
- Safety is the most important concern.
- She is the most important person on the team.
- What is the most important lesson you learned?
- Time is one of the most important resources we have.
- This may be the most important part of the project.
In each example, most important works as an adjective phrase because it describes a noun.
What Does “Most Importantly” Mean?
Most importantly is an adverbial expression. It is commonly used to introduce or emphasize the point that the speaker considers the most significant.
The base adjective is important, and the adverb is formed by adding -ly:
important → importantly
Then the superlative adverb becomes:
most importantly
For example:
Most importantly, remember to save your work.
Here, most importantly does not directly describe a noun. Instead, it comments on the entire statement that follows.
It can often be understood as:
- Above all
- More importantly than anything else
- The most significant point is
- Above everything else
Examples of “Most Importantly”
- Most importantly, be honest with yourself.
- Most importantly, follow the instructions carefully.
- We need to finish the project and, most importantly, meet the deadline.
- Most importantly, make sure everyone is safe.
- She is talented and, most importantly, hardworking.
- Most importantly, don’t give up.
Most Important vs. Most Importantly: The Main Difference
The easiest way to remember the difference is to look at the grammatical role of each expression.
| Expression | Part of speech | Main function | Example |
| Most important | Adjective phrase | Describes a noun | This is the most important rule. |
| Most importantly | Adverbial expression | Emphasizes a statement or action | Most importantly, follow the rules. |
Think of it this way:
Most important = describes a thing or person
Most importantly = emphasizes a point, action, or whole statement
That distinction will help you choose the correct expression in most situations.
When Should You Use “Most Important”?
Use most important when it directly describes a noun.
A common structure is:
the + most important + noun
For example:
This is the most important question.
The noun is question, and most important describes it.
Common Patterns With “Most Important”
You will often see most important in these structures:
- the most important thing
- the most important reason
- the most important part
- the most important person
- the most important factor
- the most important decision
- the most important lesson
- the most important goal
- the most important rule
- the most important point
Examples in Sentences
Communication is the most important skill in this job.
Here, most important describes “skill.”
This is the most important decision of my career.
Here, most important describes “decision.”
The most important thing is to remain calm.
Here, most important describes “thing.”
Trust is one of the most important parts of a healthy relationship.
Here, most important describes “parts.”
When Should You Use “Most Importantly”?
Use most importantly when you want to emphasize a statement, action, or idea.
It frequently appears at the beginning of a sentence:
Most importantly, listen carefully.
It can also appear in the middle of a sentence:
We need to work quickly and, most importantly, accurately.
It may also appear after another point:
The plan is affordable and, most importantly, practical.
In these examples, most importantly helps the reader understand that the following information has special importance.
Examples at the Beginning of a Sentence
Most importantly, be patient.
Most importantly, check the address before sending the package.
Most importantly, remember why you started.
Most importantly, everyone must follow the safety rules.
This position is especially common in formal writing, instructions, speeches, essays, and everyday conversation.
Is “Most Importantly” Grammatically Correct?
Yes. Most importantly is grammatically correct.
Some people believe that most important is always preferable because “most importantly” can sound formal or unnecessary in certain sentences. However, importantly is an established adverb, and most importantly is widely used in standard English.
For example:
Most importantly, we need to protect the children.
This is grammatically acceptable.
The expression functions as an adverbial phrase that signals the relative importance of the following statement.
However, that does not mean you can replace most important with most importantly everywhere.
For example:
This is the most important rule.
Correct.
This is the most importantly rule.
Incorrect.
The reason is simple: rule is a noun, so it needs the adjective important, not the adverb importantly.
Is “Most Important” Grammatically Correct?
Yes. Most important is also completely correct.
It is especially common when the phrase modifies a noun.
For example:
This is the most important part of the lesson.
The phrase most important describes “part.”
You can also use most important after a linking verb in certain constructions:
The most important thing is your safety.
Here, most important modifies “thing.”
Another common construction is:
What is most important is that everyone understands the instructions.
In this sentence, most important describes the idea or quality represented by “what.”
“Most Important” Without a Noun
One reason learners sometimes become confused is that most important does not always appear immediately before a noun.
For example:
What is most important is your attitude.
There is no noun immediately after most important, but the expression is still functioning adjectivally.
Another example is:
Your health is most important.
Here, most important comes after the linking verb is and describes the subject “your health.”
So, do not assume that most important must always appear before a noun.
Examples
- Your safety is most important.
- What matters most is most important? ❌
- What is most important is how you respond.
- The most important issue is cost.
- Her family is most important to her.
The exact construction determines whether the phrase works naturally.
Why Do People Confuse “Most Important” and “Most Importantly”?
The confusion comes from the fact that important and importantly are closely related.
The basic difference is:
- Important = adjective
- Importantly = adverb
Compare these examples:
This is important.
“Important” describes this.
She spoke importantly about the issue.
“Importantly” modifies the verb or manner of speaking, although this particular use is less common in everyday English.
But most importantly has developed a very common discourse function. It often introduces the speaker’s main or highest-priority point.
For example:
Most importantly, don’t forget your passport.
Here, the phrase does not mean that the person is performing the action “forget” importantly. Instead, it signals the importance of the entire instruction.
Most Important or Most Importantly at the Beginning of a Sentence?
When you want to introduce the main point, most importantly is usually the natural choice.
For example:
Most importantly, you need to be honest.
This tells the reader that honesty is the highest-priority point.
However, most important can also appear in certain sentence structures:
Most important is your willingness to learn.
This is grammatical but sounds more formal or literary.
A more natural everyday version would be:
The most important thing is your willingness to learn.
Therefore, if you are starting a sentence and want to say “above all,” most importantly is often the clearest option.
Most Important or Most Importantly After a Comma?
Both can appear near commas, but they work differently.
Most Important
The most important thing, however, is consistency.
Here, most important describes “thing.”
Most Importantly
We need consistency and, most importantly, patience.
Here, most importantly acts as an interrupting adverbial phrase.
You can also write:
Most importantly, we need patience.
The comma after most importantly is standard when the phrase introduces the sentence.
Can You Say “And Most Importantly”?
Yes.
And most importantly is a common construction.
For example:
The plan must be simple, affordable, and, most importantly, effective.
Another example:
He was kind, helpful, and most importantly, honest.
For maximum clarity, especially in formal writing, commas can set off most importantly when it functions as an interrupter:
He was kind, helpful, and, most importantly, honest.
The punctuation style can vary depending on sentence structure and editorial preference.
Can You Say “But Most Importantly”?
Yes.
But most importantly is also common when the writer wants to emphasize a final or more significant point.
For example:
The product is affordable, easy to use, and, most importantly, reliable.
Or:
We can make mistakes, but most importantly, we should learn from them.
The phrase helps transition from a secondary point to the point the writer considers more significant.
Can You Say “Most Importantly of All”?
Yes.
Most importantly of all is grammatically possible and emphasizes the highest priority.
For example:
Most importantly of all, everyone must remain safe.
However, in many situations, most importantly is enough.
Compare:
Most importantly, everyone must remain safe.
Most importantly of all, everyone must remain safe.
The second version adds extra emphasis, but it can sound slightly more dramatic or wordy.
Most Important vs. More Important
Another common mistake is confusing most important with more important.
They do not mean exactly the same thing.
More Important
More important compares two things or groups.
Health is more important than money.
This sentence compares health and money.
Most Important
Most important identifies the highest level among three or more things or among a larger group.
Health is the most important thing in life.
The sentence presents health as having the greatest importance.
Simple Comparison
| Phrase | Meaning | Example |
| Important | Has significance | This rule is important. |
| More important | Has greater significance than another | Safety is more important than speed. |
| Most important | Has the greatest significance | Safety is the most important factor. |
Most Important vs. Importantly
The difference becomes clearer when you remove most.
Important is an adjective:
This point is important.
Importantly is an adverb:
Importantly, this point affects everyone.
The first sentence describes the point itself.
The second uses importantly to emphasize the statement.
Adding most creates:
the most important point
and:
most importantly, this affects everyone.
Common Mistake: “Most Importantly Thing”
One of the most frequent errors is using most importantly before a noun.
Incorrect:
This is the most importantly thing.
Correct:
This is the most important thing.
Why?
Because thing is a noun, and the word describing it must be an adjective.
Important = adjective
Importantly = adverb
So remember:
most important + noun
Not:
most importantly + noun
Common Mistake: “The Most Importantly”
Another error is writing the most importantly when you need an adjective.
Incorrect:
This is the most importantly part.
Correct:
This is the most important part.
However, most importantly can stand at the beginning of a sentence without the:
Most importantly, follow the instructions.
Therefore:
- the most important part ✅
- most importantly, follow the instructions ✅
- the most importantly part ❌
Common Mistake: Using “Importantly” When “Important” Is Needed
Consider this sentence:
Family is most importantly to me.
This sounds incorrect because the speaker wants to describe the importance of family.
Better:
Family is most important to me.
Or:
Most importantly, I want my family to be happy.
The first sentence describes family. The second emphasizes the statement.
Common Mistake: Thinking “-ly” Always Means “More Correct”
English learners sometimes assume that adding -ly makes a word more sophisticated or grammatically correct.
That is not how English works.
The suffix -ly often changes an adjective into an adverb:
- quick → quickly
- careful → carefully
- clear → clearly
- important → importantly
But you should not automatically use the adverb whenever you see a similar sentence.
The word must match its grammatical function.
Most Important in Questions
Most important is very common in questions.
Examples:
What is the most important thing to remember?
What is the most important part of the process?
Who is the most important person in your life?
What is the most important factor to consider?
Which is the most important reason for this decision?
These questions ask the reader to identify the thing with the greatest importance.
Most Importantly in Instructions
Most importantly is particularly useful when giving advice or instructions.
Examples:
Most importantly, read the instructions before starting.
Most importantly, keep your password private.
Most importantly, don’t panic.
Most importantly, check your work before submitting it.
The expression tells the reader that the following instruction deserves special attention.
Most Important in Academic Writing
Most important is common in academic and formal writing when it modifies a noun.
Examples:
The most important factor is access to education.
One of the most important findings concerns consumer behavior.
The most important limitation of the study is its small sample size.
This represents one of the most important changes in the field.
Most importantly can also appear in academic writing, particularly when emphasizing a point:
Most importantly, the findings suggest that additional research is necessary.
However, academic writers should use it naturally rather than inserting it into every paragraph.
Most Important in Everyday English
You will hear most important frequently in normal conversation.
For example:
The most important thing is that you’re okay.
What’s the most important thing for you?
Your health is most important.
That’s the most important part.
These sentences sound natural and straightforward.
Most Importantly in Everyday English
You will also hear most importantly in conversation, especially when someone lists priorities.
For example:
First, we need to finish the report. Most importantly, we need to check the numbers.
You should bring your phone, some water, and most importantly, your ID.
Most importantly, don’t forget to have fun.
It works especially well when someone wants to highlight a final point.
A Simple Trick to Remember the Difference
Use this simple question:
Am I describing a noun?
If yes, use most important.
The most important rule.
The most important reason.
The most important person.
If you are emphasizing an entire statement or action, use most importantly.
Most importantly, follow the rule.
Most importantly, understand the reason.
Most importantly, treat people with respect.
Easy Memory Formula
Most important + thing
Most importantly + idea/action
This isn’t a rule that covers every possible grammatical construction, but it is an excellent shortcut for everyday writing.
Examples: Correct vs. Incorrect
| Incorrect | Correct | Reason |
| The most importantly thing | The most important thing | “Important” describes “thing.” |
| The most importantly reason | The most important reason | “Important” describes “reason.” |
| This is most importantly | This is most important | “Important” works as a complement here. |
| Most important, be careful. | Most importantly, be careful. | “Most importantly” introduces the emphasized instruction. |
| The most importantly factor | The most important factor | “Important” describes “factor.” |
| Most important, remember this. | Most importantly, remember this. | Adverbial emphasis is needed. |
Most Important or Most Importantly in Professional Writing?
Both can be appropriate in professional writing.
Use most important when describing a specific factor, requirement, objective, or element.
For example:
The most important requirement is accuracy.
Use most importantly when highlighting a key point.
For example:
Most importantly, the final report must be accurate.
The choice depends on sentence structure rather than whether the writing is formal or informal.
Most Important or Most Importantly in Emails?
Both expressions work in emails.
Using “Most Important”
The most important issue is the deadline.
Using “Most Importantly”
Most importantly, please confirm the deadline before Friday.
If you’re listing several considerations, most importantly can make the priority clear.
Most Important or Most Importantly in Essays?
Both can be used in essays, but they serve different purposes.
Use most important to describe a noun:
The most important factor influencing the results was sample size.
Use most importantly to emphasize a conclusion or point:
Most importantly, the results demonstrate the need for further research.
Avoid repeating the same expression too frequently. Good writing varies sentence structures naturally.
“Most Important Thing” vs. “Most Importantly”
These expressions are sometimes confused because they can communicate a similar idea.
Compare:
The most important thing is to stay calm.
Most importantly, stay calm.
Both sentences emphasize staying calm, but their grammar differs.
In the first sentence:
most important describes thing.
In the second sentence:
most importantly emphasizes the instruction stay calm.
Both can be useful, depending on the structure you want.
Is “Most Important” an Adjective?
Yes.
Important is an adjective, and most important is a superlative adjective phrase.
For example:
This is the most important lesson.
The adjective phrase describes lesson.
It can also appear after a linking verb:
This lesson is most important.
Although the second construction is grammatical, This lesson is the most important is often more natural when comparing it with other lessons.
Is “Most Importantly” an Adverb?
Yes, in its common sentence-level use, most importantly functions as an adverbial expression.
It commonly modifies or comments on the statement that follows.
For example:
Most importantly, we need to protect the environment.
It does not describe a particular noun such as “environment.”
Instead, it signals the importance of the entire proposition.
Spelling Tips for “Important” and “Importantly”
The spelling is straightforward, but learners sometimes make mistakes when adding -ly.
The correct forms are:
- important
- importantly
- more important
- most important
- more importantly
- most importantly
Incorrect forms include:
- importantely ❌
- importently ❌
- most importent ❌
- most importantely ❌
A useful spelling reminder is:
important + ly = importantly
The base word remains important.
How to Use “More Importantly”
Although your main question may be about most important and most importantly, it helps to understand more importantly because the expressions are closely related.
More importantly is generally used to introduce a point that the speaker considers more significant than the previous point.
For example:
The product is affordable. More importantly, it is reliable.
Here, reliability is presented as more significant than affordability.
Compare:
More importantly, the product is reliable.
with:
Most importantly, the product is reliable.
More importantly often creates a comparison with something already mentioned.
Most importantly highlights the highest-priority point.
Most Important and Most Importantly in Lists
When listing several qualities, you may use most important before a noun:
The most important qualities are honesty, patience, and reliability.
You can also use most importantly to highlight one quality:
Honesty and patience matter. Most importantly, you need to be reliable.
This difference is useful in presentations and explanatory writing.
Sentence Practice
Here are several examples to help you recognize the difference.
Example 1
This is the most important decision of the year.
Most important describes decision.
Example 2
Most importantly, make the decision carefully.
Most importantly emphasizes the instruction.
Example 3
Education is one of the most important investments a person can make.
Most important describes investments.
Example 4
Most importantly, education should be accessible.
Most importantly emphasizes the statement.
Example 5
The most important goal is customer satisfaction.
Most important describes goal.
Example 6
Most importantly, listen to your customers.
Most importantly emphasizes the action.
How to Choose the Correct Expression Quickly
When you’re writing and suddenly wonder which phrase to use, follow these three steps.
Step 1: Find the Main Word
Look at the word that important is connected to.
If it is a noun, most important is often correct.
the most important factor
Step 2: Check the Sentence’s Purpose
Ask whether you’re emphasizing a complete statement.
If yes, most importantly may be the right choice.
Most importantly, we need to act now.
Step 3: Remove “Most”
If you’re still uncertain, remove most.
Would important make sense?
This is important.
Then most important may be appropriate.
Would importantly make sense as an introductory adverb?
Importantly, this affects everyone.
Then most importantly may be appropriate.
Frequently Asked Questions
Is “most importantly” correct English?
Yes. Most importantly is a standard and grammatically acceptable expression. It commonly introduces or emphasizes the most significant point in a statement.
Is “most important” correct English?
Yes. Most important is a superlative adjective phrase used to describe something that has the greatest importance.
Which is correct: “most important” or “most importantly”?
Both are correct, but they have different grammatical functions. Use most important when describing a noun or functioning as an adjective complement. Use most importantly when emphasizing a statement or point.
Should I say “the most important” or “the most importantly”?
Usually, say the most important when a noun follows.
The most important thing.
The most important reason.
The most important factor.
The most importantly is generally incorrect in these constructions.
Is “most importantly” an adverb?
Yes. In expressions such as “Most importantly, remember this,” it functions as an adverbial expression that emphasizes the following statement.
Can I start a sentence with “most importantly”?
Yes. This is very common.
Most importantly, make sure you understand the instructions.
A comma normally follows the introductory expression.
Can I start a sentence with “most important”?
Yes, but the construction may sound more formal or incomplete unless the sentence is structured correctly.
Most important is your safety.
This is grammatical, but:
The most important thing is your safety.
sounds more natural in everyday English.
Can I use “most importantly” before a noun?
Generally, no, when you are trying to describe that noun.
Incorrect:
The most importantly point.
Correct:
The most important point.
What is the difference between “more important” and “most important”?
More important normally compares two things or groups, while most important identifies the highest level of importance.
Health is more important than money.
Health is the most important thing.
What is the difference between “more importantly” and “most importantly”?
More importantly often introduces something considered more significant than a previously mentioned point. Most importantly highlights the point considered the highest priority.
Is “most importantly” too formal?
Not necessarily. It appears in formal writing, professional communication, speeches, and everyday conversation. However, simple alternatives such as above all or most of all may sometimes sound more conversational.
Can I replace “most important” with “most importantly”?
No. You cannot replace them mechanically because they have different grammatical functions.
This is the most important rule. ✅
This is the most importantly rule. ❌
Can I replace “most importantly” with “most important”?
Not in every sentence.
Most importantly, follow the rules. ✅
Most important, follow the rules. ⚠️
The second version can occur in some formal constructions, but most importantly is the natural choice for this sentence.
Final Thought
The difference between most important and most importantly is mainly grammatical. Most important is an adjective phrase. It describes a noun or identifies something as having the highest level of importance. This is the most important rule.
Most importantly is an adverbial expression. It highlights the point that the speaker considers especially or ultimately significant. Most importantly, follow the rules. When you see a noun such as thing, reason, factor, point, person, rule, goal, or decision, most important will often be the correct choice.
Michael Collins is a skilled writer who creates clear, practical, and reader-friendly content. He focuses on language, grammar, word meanings, and everyday expressions, making complex topics simple to understand.
