Have you ever paused while writing and wondered whether you should use complaint or complain? You’re not alone. These two words are closely related, but they serve completely different roles in English grammar.

Understanding complaint vs complain is essential for speaking and writing correctly, whether you’re sending a customer service email, writing an academic paper, or simply having a conversation. In this guide, you’ll learn the meaning of each word, when to use it, common mistakes to avoid, memory tricks, and plenty of real-world examples.

What Is the Difference Between Complaint and Complain?

The simplest difference is this:

• Complaint is a noun.
• Complain is a verb.

In other words:

• A complaint is the problem or expression of dissatisfaction.
• To complain means to express dissatisfaction.

Think of it this way:

You complain by making a complaint.

This relationship is similar to:

• Decide → Decision
• Respond → Response
• Apply → Application

The action comes first (verb), while the result or thing is the noun.

Complaint Meaning

A complaint is a statement expressing that something is wrong, unsatisfactory, or unfair.

It refers to the issue itself rather than the action of expressing it.

Examples

• The customer filed a complaint about the delayed delivery.
• We received several complaints regarding the noise.
• Her biggest complaint was the poor customer service.
• The hospital addressed every patient complaint promptly.

In each sentence, complaint is the object or thing being discussed.

Complain Meaning

Complain means to express dissatisfaction, annoyance, or disappointment about something.

It describes the action someone performs.

Examples

• Customers often complain about long waiting times.
• Don’t complain before trying to solve the problem.
• She never complains, even when work becomes difficult.
• They complained about the expensive tickets.

Notice that complain shows an action.

Complaint vs Complain: Side-by-Side Comparison

When Should You Use “Complaint”?

Use complaint whenever you’re referring to:

• A report of a problem
• A formal grievance
• A written or spoken objection
• The issue itself

Common situations

• Customer complaints
• Workplace complaints
• Legal complaints
• Product complaints
• Medical complaints

Examples

• The company investigated every complaint carefully.
• Please submit your complaint online.
• His complaint was resolved within two days.
• There were no complaints after the update.

When Should You Use “Complain”?

Use complain whenever someone is expressing dissatisfaction.

It usually appears with words like:

• about
• of
• that
• to

Examples

• They complained about the food.
• She complained to the manager.
• Many people complain that prices are rising.
• He complained of severe headaches.

Grammar Rules for Complaint and Complain

Understanding their grammatical role makes choosing the correct word much easier.

Complaint Is a Noun

A noun names:

• a person
• a place
• a thing
• an idea

Since complaint is a thing, it can be:

• singular
• plural
• modified by adjectives
• preceded by articles

Examples:

• a complaint
• several complaints
• a formal complaint
• your complaint

Complain Is a Verb

A verb shows an action.

It changes depending on tense.

Present

• I complain
• You complain
• They complain

Third Person

• She complains

Past

• They complained

Continuous

• He is complaining.

Common Expressions Using Complaint

English speakers frequently use these phrases:

• file a complaint
• make a complaint
• submit a complaint
• receive a complaint
• investigate a complaint
• customer complaint
• official complaint
• formal complaint
• noise complaint

Example

The manager handled every customer complaint professionally.

Common Expressions Using Complain

You’ll often hear:

• complain about
• complain to
• complain of
• complain that
• constantly complain
• frequently complain

Example

Customers complain about slow internet speeds during peak hours.

Real-Life Examples

In Customer Service

Correct:

• I’d like to make a complaint.
• I’d like to complain about my order.

Incorrect:

• I’d like to make a complain.
• I’d like to complaint about my order.

In School

Correct:

• The student filed a complaint against bullying.
• Students often complain about difficult exams.

At Work

Correct:

• HR received a formal complaint.
• Employees complained about overtime policies.

In Healthcare

Correct:

• The patient complained of chest pain.
• The doctor reviewed the patient’s chief complaint.

Common Mistakes People Make

Mistake 1

Incorrect: I want to complaint.

Correct: I want to complain.

Mistake 2

Incorrect: She made a complain.

Correct: She made a complaint.

Mistake 3

Incorrect: They complaint every day.

Correct: They complain every day.

Mistake 4

Incorrect: He submitted a complain.

Correct: He submitted a complaint.

Easy Memory Trick

Here’s a simple way to remember the difference.

Complain = Action

If someone is doing something, use complain.

Example:

She likes to complain.

Complaint = Thing

If you’re talking about the issue itself, use complaint.

Example:

Her complaint was resolved quickly.

Think of it this way:

Complain is what you do.
Complaint is what you make.

Synonyms of Complaint

Depending on context:

• grievance
• objection
• criticism
• protest
• concern
• accusation
• issue
• report

Synonyms of Complain

Possible alternatives include:

• protest
• object
• criticize
• grumble
• moan
• whine
• express dissatisfaction
• voice concerns

Complaint vs Complain in Formal Writing

Formal writing usually prefers specific phrases.

Examples:

• submit a complaint
• file a complaint
• investigate complaints
• complain formally
• complain to the authorities

Business emails, legal documents, and customer support communications often distinguish clearly between the action (complain) and the document or issue (complaint).

Everyday Conversation Examples

Friend:

“I always complain when my coffee is cold.”

Restaurant:

“The manager apologized after receiving our complaint.”

Office:

“Employees shouldn’t hesitate to complain if policies are unfair.”

School:

“The teacher addressed every complaint respectfully.”

Quick Practice Quiz

Choose the correct word.

1.

I’d like to ______ about the delayed package.

 complain

2.

The company received a customer ______.

 complaint

3.

Why do people always ______ about the weather?

 complain

4.

Your ______ has been forwarded to our support team.

 complaint

Key Takeaways

• Complaint is a noun that refers to a problem, grievance, or expression of dissatisfaction.
• Complain is a verb that means to express dissatisfaction.
• You make, submit, or file a complaint.
• You complain about, complain of, or complain to someone.
• Choosing the correct word improves clarity in both formal and everyday English.

Frequently Asked Questions

Is it “complaint” or “complain”?

It depends on the sentence. Use complaint when referring to the issue or grievance, and use complain when describing the act of expressing dissatisfaction.

Can complaint be used as a verb?

No. Complaint is only a noun. If you need an action word, use complain.

What is the easiest way to remember complaint vs complain?

Remember this phrase: You complain by making a complaint. The verb describes the action, while the noun names the issue.

Is “make a complaint” grammatically correct?

Yes. “Make a complaint” is the standard and widely accepted expression in both spoken and written English.

Can I say “file a complain”?

No. The correct phrase is file a complaint because you’re filing the grievance, not the action.

Why do English learners confuse complaint and complain?

They share the same root word and have similar spellings, making them easy to mix up. Remembering that complain is the action and complaint is the result helps avoid this common mistake.

Conclusion

The difference between complaint vs complain is straightforward once you understand their grammatical roles. Complain is the verb used when someone expresses dissatisfaction, while complaint is the noun referring to the concern or grievance itself. Using the correct word makes your communication more accurate, professional, and natural.

The next time you’re writing an email, speaking with customer support, or helping someone learn English, remember this simple rule: you complain by making a complaint. Mastering this distinction will help you avoid common grammar mistakes and communicate with greater confidence.