Complaint vs Complain: Meaning, Difference, And Correct Usage

English contains many words that look or sound similar but serve different purposes in a sentence. Sometimes, the difference between two words is as simple as a change in spelling. In other cases, it involves an important grammatical distinction that can affect the meaning and clarity of a sentence. “Complaint” vs “complain” are two such words that frequently confuse English learners, students, professionals, and even native speakers when writing quickly.

Although both words are closely related in meaning, they are not interchangeable. The word “complaint” is a noun, while “complain” is a verb. In simple terms, a complaint is an expression of dissatisfaction, while to complain means to express dissatisfaction.

For example, consider these two sentences:

• “I want to make a complaint about the poor customer service.”
• “I want to complain about the poor customer service.”

Both sentences communicate dissatisfaction, but they use different grammatical structures. In the first sentence, complaint names the action or expression of dissatisfaction. In the second, complain describes the action itself.

Understanding this distinction is essential for writing professional emails, submitting formal grievances, communicating with customer service representatives, preparing academic assignments, and speaking English naturally.

This article explains the meaning of complaint and complain, their grammatical differences, the rules governing their usage, common mistakes to avoid, and practical examples from everyday life. It also includes realistic scenarios involving emails, workplace communication, customer service, education, travel, and personal relationships to help you understand how to use both words correctly.

What Does “Complaint” Mean?

The word “complaint” is a noun that refers to an expression of dissatisfaction, an objection, or a statement that something is wrong, unfair, unpleasant, or unsatisfactory.

A complaint may be expressed verbally, in writing, through an official form, or by submitting a formal report to an appropriate authority.

People make complaints for many reasons. A customer may complain about a defective product, an employee may submit a complaint about unfair treatment, or a tenant may raise a complaint about a leaking roof.

In each situation, the word complaint refers to the expression, statement, or formal record of dissatisfaction.

Simple Definition of Complaint

Complaint (noun): An expression of dissatisfaction about a person, situation, service, product, or experience.

Here are some examples:

• “The customer submitted a complaint about the damaged package.”
• “Our manager received a complaint about the employee’s behaviour.”
• “I have a complaint regarding the noise coming from the neighbouring apartment.”
• “The school investigated the parent’s complaint.”
• “She filed a formal complaint against the company.”

Notice that the word complaint is used as a thing or concept in each sentence. It is something a person can submit, receive, investigate, file, or discuss.

Common Expressions Using “Complaint”

Certain words frequently appear alongside complaint. Learning these expressions will help you write more naturally and professionally.

• Make a complaint: To express dissatisfaction.
• File a complaint: To submit an official complaint.
• Lodge a complaint: To formally submit a complaint, especially in British and international English.
• Submit a complaint: To present a complaint to an organisation or authority.
• Receive a complaint: To be informed that someone is dissatisfied.
• Register a complaint: To officially record a complaint.
• Handle a complaint: To manage or respond to a complaint.
• Investigate a complaint: To examine the facts behind a complaint.
• Resolve a complaint: To address the problem and reach a satisfactory outcome.
• Withdraw a complaint: To formally take back a complaint.

Examples:

1. “I would like to make a complaint about the delay in my order.”
2. “The customer decided to file a complaint with the consumer protection office.”
3. “The hotel manager promised to investigate the complaint immediately.”
4. “Our support team works hard to resolve customer complaints within 48 hours.”
5. “After receiving a refund, the customer agreed to withdraw the complaint.”

These expressions are especially useful in formal communication because they make the nature of the action clear.

Read More: Guidance vs Guidence: Correct Spelling, Meaning And Usage Guide

What Does “Complain” Mean?

The word “complain” is a verb. It describes the action of expressing dissatisfaction, annoyance, discomfort, or objection about something.

When you complain, you communicate that you are unhappy with a particular situation or believe something needs to change.

For instance, if a passenger tells an airline employee that their luggage has been lost, the passenger is complaining about the situation. If an employee tells a supervisor that the workload is unfair, the employee is complaining about working conditions.

Unlike complaint, which names the expression of dissatisfaction, complain describes what a person does.

Simple Definition of Complain

Complain (verb): To express dissatisfaction, annoyance, or unhappiness about something.

Examples:

• “Customers often complain about long waiting times.”
• “She decided to complain to the manager.”
• “The residents complained about the loud music.”
• “He is always complaining about his workload.”
• “Several passengers have complained about the cancellation.”

The word changes its form according to tense and grammatical structure. For example, complain is the base form, complains is the third-person singular present form, complained is the simple past and past participle, and complaining is the present participle or gerund form.

Common Expressions Using “Complain”

Here are some frequently used expressions with complain:

• Complain about something: Express dissatisfaction with a situation or thing.
• Complain to someone: Express dissatisfaction to a person or authority.
• Complain of something: Report a symptom, discomfort, or problem.
• Complain that something happened: Express dissatisfaction through a statement or explanation.
• Complain formally: Express dissatisfaction through an official procedure.
• Complain repeatedly: Express dissatisfaction several times.

Examples:

1. “The residents complained about the traffic noise.”
2. “I will complain to the supervisor if the problem continues.”
3. “The patient complained of severe stomach pain.”
4. “She complained that the instructions were unclear.”
5. “Several employees complained formally about the new policy.”

An important point is that complain is an action word, so it usually needs to fit into a verb structure. You can say “I complained yesterday,” “I am complaining now,” or “I will complain tomorrow.”

Complaint vs Complain: The Main Difference

The most important difference between these two words is their part of speech.

Feature	Complaint	Complain
Part of speech	Noun	Verb
Meaning	An expression of dissatisfaction	To express dissatisfaction
Common use	Name of a concern or grievance	Action of expressing dissatisfaction
Common expressions	Make, file, submit, receive a complaint	Complain about, complain to, complain that
Example	“I submitted a complaint.”	“I complained to the manager.”
Plural or tense forms	Complaints	Complains, complained, complaining

The difference becomes clearer when the words are used to communicate the same idea.

Using “complaint”:

“Daniel submitted a complaint about the poor internet connection.”

Here, complaint is the noun that identifies what Daniel submitted.

Using “complain”:

“Daniel complained about the poor internet connection.”

Here, complained is the verb describing what Daniel did.

Both sentences are correct, but their grammatical structures are different.

An Easy Way to Remember the Difference

Think of the distinction this way:

• Complaint = the thing.
• Complain = the action.

You can make a complaint, write a complaint, receive a complaint, or investigate a complaint.

You can complain about a problem, complain to a manager, or complain that something is unfair.

A useful memory trick is to compare the words advice and advise. In that pair, advice is a noun and advise is a verb. Similarly, complaint is a noun and complain is a verb, although the spelling difference is slightly different.

Read More: Lent vs Lended: Which Is Correct? Rules And Examples

How to Use “Complaint” Correctly in Sentences

To use complaint correctly, remember that it is a noun. It can appear as the subject or object of a sentence, follow certain verbs, or be used after articles and possessive words.

1. Using “Complaint” After an Article

A singular countable noun usually requires a determiner, such as a, an, or the, when it is used in a typical sentence.

Examples:

• “I have a complaint about the service.”
• “The manager investigated the complaint.”
• “She submitted a formal complaint yesterday.”
• “He ignored the customer’s complaint.”

In these sentences, a complaint refers to one complaint that is being introduced, while the complaint refers to a particular complaint that is already known or has been identified.

Incorrect: “I want to make complaint.”
Correct: “I want to make a complaint.”

The article a is necessary in this sentence because complaint is a singular countable noun.

2. Using “Complaint” as the Object of a Verb

The word complaint frequently follows verbs such as make, file, submit, receive, and investigate.

Examples:

• “The tenant filed a complaint against the landlord.”
• “The company received several complaints from its customers.”
• “The supervisor investigated the complaint.”
• “I would like to submit a complaint regarding the billing error.”

In each example, the noun identifies the issue being reported or handled.

3. Using “Complaint” with Prepositions

The preposition used with complaint depends on the meaning you want to communicate.

Complaint about: Used to identify the subject of dissatisfaction.

• “I have a complaint about the delivery service.”
• “Several parents submitted complaints about the school timetable.”

Complaint against: Often used when a complaint is directed at a person, company, organisation, or authority.

• “She filed a complaint against her employer.”
• “The customer lodged a complaint against the insurance company.”

Complaint regarding: A formal alternative to complaint about.

• “I am writing to submit a complaint regarding my recent electricity bill.”

Complaint to: Identifies the person or organisation receiving the complaint.

• “He submitted a complaint to the regional manager.”
• “We sent our complaint to the customer relations department.”

Choosing the correct preposition helps make your sentence precise.

4. Using “Complaint” in the Plural Form

The plural of complaint is complaints.

Examples:

• “The restaurant has received numerous complaints about its slow service.”
• “The authorities investigated three separate complaints.”
• “Customer complaints increased during the holiday season.”

Do not write complaint’s when you simply mean more than one complaint. An apostrophe normally indicates possession or a contraction, not a regular plural.

Incorrect: “The company received many complaint’s.”
Correct: “The company received many complaints.”

How to Use “Complain” Correctly in Sentences

Since complain is a verb, it must fit the tense and structure of the sentence.

1. Using “Complain” in the Present Tense

Use complain with plural subjects and with I, you, and we. Use complains with third-person singular subjects such as he, she, and it.

Examples:

• “I often complain about poor customer service.”
• “They complain about the cost of transport.”
• “We complain when the quality does not meet expectations.”
• “She complains about everything.”
• “My neighbour complains about the noise.”

The difference between complain and complains is a basic subject-verb agreement rule.

Incorrect: “She complain about the food.”
Correct: “She complains about the food.”

2. Using “Complain” in the Past Tense

The simple past form of complain is complained.

Examples:

• “I complained to the receptionist yesterday.”
• “The customers complained about the damaged products.”
• “Amir complained that his salary was incorrect.”
• “We complained about the delay, but nobody responded.”

The past form remains complained regardless of whether the subject is singular or plural.

3. Using “Complain” in Continuous Tenses

Use complaining with the appropriate form of the verb be when describing an ongoing action.

Examples:

• “The customer is complaining about the price.”
• “The passengers were complaining about the temperature.”
• “She has been complaining about her workload all week.”

The continuous form emphasises that the act of expressing dissatisfaction is happening or has continued over a period.

4. Using “Complain About”

The expression complain about is one of the most common grammatical patterns involving this verb.

Use it when identifying the issue, experience, person, or situation causing dissatisfaction.

Examples:

• “The residents complained about the water shortage.”
• “My colleague complains about the office temperature.”
• “The customer is complaining about the incorrect charge.”

You can also use a noun phrase or a verb ending in -ing after about.

• “She complained about the delay.”
• “She complained about waiting for two hours.”

Both structures are grammatically correct.

5. Using “Complain To”

Use complain to when you want to identify the person or organisation to whom dissatisfaction is expressed.

Examples:

• “I complained to the manager.”
• “The students complained to their teacher.”
• “Several residents complained to the local authorities.”

A useful distinction is:

• Complain about the problem.
• Complain to the person responsible for addressing it.

For example, “I complained to the manager about the broken air conditioner.”

Here, to the manager identifies the recipient, while about the broken air conditioner identifies the problem.

6. Using “Complain That”

The word that can introduce the statement explaining why someone is dissatisfied.

Examples:

• “The employee complained that the workload was unreasonable.”
• “The customer complained that the parcel had arrived late.”
• “Mariam complained that nobody had informed her about the change.”

In everyday English, that is sometimes omitted without changing the basic meaning.

For example:

“The customer complained the parcel had arrived late.”

This construction is possible, but including that often makes formal writing clearer.

Read More: Humorous vs Humerous: Which Spelling Is Correct?

Complaint vs Complain in Professional Emails

Professional emails are one of the most common situations in which these words are used incorrectly. A well-written complaint email should clearly identify the issue, explain what happened, and state the action you expect the recipient to take.

Scenario 1: Writing a Formal Complaint Email

Imagine that you purchased a laptop online, but it arrived with a cracked screen.

In this situation, you may write a formal email to the seller.

Why is “complaint” correct here?

The writer is submitting a formal expression of dissatisfaction. Therefore, complaint functions as a noun in the phrase “make a formal complaint.”

The sentence “I am writing to complain about the laptop” would also be correct. In that version, complain is the verb describing the purpose of the email.

Scenario 2: Telling a Manager That You Want to Complain

Suppose an employee has repeatedly experienced problems with the office heating system and wants to speak to a manager before submitting a formal grievance.

The employee could write:

Why is “complain” correct here?

The employee is describing an action they may take in the future. The verb complain follows the modal verb may, so it appears in its base form.

Notice that we write “may complain,” not “may complains” or “may complained.”

Scenario 3: Responding to a Customer Complaint

Imagine that you work in customer service and receive an email from a customer who has been charged twice for one purchase.

A suitable response might be:

Why is “complaint” correct here?

The email refers to a particular issue that the customer reported. The phrase “your complaint about the billing error” uses complaint as a noun.

The expression complain about the billing error would describe the customer’s action rather than identify the reported case.

Complaint vs Complain in Everyday Situations

The distinction is not limited to offices and formal correspondence. Both words appear frequently in conversations about food, transport, shopping, education, and personal experiences.

Scenario 4: Complaining at a Restaurant

Suppose you visit a restaurant with a friend, and your meal arrives cold.

You could say to the waiter:

“Excuse me, I would like to complain about the temperature of my meal. I ordered this food a few minutes ago, but it has arrived cold. Would it be possible to have it reheated or replaced?”

Here, complain is the verb because you are expressing dissatisfaction.

You could also say:

“I have a complaint about my meal.”

In this sentence, complaint is a noun because you are identifying the concern you wish to raise.

Both expressions are correct. However, in a real restaurant, politely explaining the problem and requesting a solution will usually be more constructive than simply announcing that you want to complain.

Scenario 5: Complaining About Public Transport

Imagine that a bus arrives 45 minutes late, causing you to miss an important appointment.

You might tell a friend:

“I had to complain to the transport office because the bus was extremely late.”

Alternatively, you might say:

“I submitted a complaint about the bus service because the bus was extremely late.”

The first sentence focuses on the action of expressing dissatisfaction. The second focuses on the complaint that was submitted.

For a formal letter, you could write:

The noun complaint is particularly suitable in formal correspondence because it identifies the matter being presented for review.

Scenario 6: A Student Complaining About an Examination Result

Suppose a student believes that a teacher has recorded the wrong examination score.

The student might speak to the teacher:

“Excuse me, I would like to complain about my examination result because I believe one of my answers may not have been marked.”

However, a more constructive approach in an academic setting might be:

“I would like to raise a concern about my examination result. Could you please help me understand how the marks were calculated?”

The second version avoids sounding unnecessarily confrontational while still communicating the concern.

If the student submits an official request, the wording could be:

“I am submitting a formal complaint regarding my examination result and requesting a review of the marking process.”

The appropriate expression depends on the seriousness of the issue and the procedure established by the school or university.

Scenario 7: Complaining About a Neighbour’s Noise

Suppose your neighbour plays loud music late at night.

You might tell another neighbour:

“I have tried speaking to him, but he continues to play loud music. I may need to complain to the building manager.”

If you want to describe the issue itself, you could say:

“I have a complaint about the noise coming from the apartment upstairs.”

The difference remains the same: complain expresses the action, while complaint names the grievance.

In a written message to the building manager, you could write:

Notice that you do not have to use either word in every complaint-related message. Sometimes, “report a problem,” “raise a concern,” or “request assistance” communicates the issue more naturally.

Read More: Tomorrow vs Tommorow: Which Spelling Is Correct?

Complaint vs Complain in Workplace Communication

Workplace communication often requires a careful balance between expressing dissatisfaction and maintaining professional relationships. Understanding the distinction between these words helps employees, managers, and human resources professionals communicate more precisely.

Scenario 8: An Employee Complaining About an Unfair Workload

Imagine that an employee has been assigned additional responsibilities without a reasonable adjustment to deadlines.

The employee might tell a colleague:

“I have been complaining about my workload for weeks, but nothing has changed.”

Here, complaining is the continuous form of the verb complain. It describes an ongoing action.

If the employee submits a written grievance, the wording might be:

“I would like to submit a formal complaint about the distribution of work within our department.”

The noun complaint is appropriate because the employee is referring to a formal document or grievance.

Scenario 9: A Manager Discussing Customer Complaints

Suppose a manager is reviewing feedback about a company’s delivery service.

The manager might tell the team:

“We have received several complaints about late deliveries this month. We need to identify the cause and improve our delivery process.”

Alternatively, the manager might say:

“Customers continue to complain about late deliveries, so we need to act quickly.”

The first sentence identifies the reports received. The second describes what customers are doing.

Both statements are correct, and choosing between them depends on whether the emphasis is on the reports or on the customers’ actions.

Scenario 10: An Employee Complaining About a Colleague

Imagine that an employee believes a colleague repeatedly takes credit for other people’s work.

The employee might say to a supervisor:

“I would like to raise a concern about how responsibilities are being acknowledged within the team.”

If the issue requires a formal investigation, the employee might instead write:

“I would like to submit a formal complaint regarding repeated incidents of misattributed work.”

The distinction matters, but so does the tone. A professional complaint should ideally focus on specific behaviour, verifiable facts, and the desired resolution rather than personal attacks.

Complaint vs Complain in Health and Medical Contexts

The verb complain is also used in medical settings, particularly when describing symptoms or discomfort reported by a patient.

For example:

• “The patient complained of severe abdominal pain.”
• “The child complained of a headache.”
• “The patient is complaining about persistent discomfort.”

In medical and formal reporting, “complain of” is a traditional and common construction used to report a symptom or physical sensation.

Compare the following examples:

“The patient complained of chest pain.”

This sentence reports a symptom.

“The patient made a complaint about the hospital’s waiting time.”

This sentence refers to dissatisfaction with the service received.

The first uses complained as a verb, while the second uses complaint as a noun.

It is important to distinguish between reporting a symptom and expressing dissatisfaction with a service. Although the same word family can be used in both contexts, the intended meaning differs.

Complaint vs Complain in Formal Letters and Official Reports

Official letters often use complaint because it clearly identifies the purpose of the document. This is common in communications with landlords, banks, government departments, service providers, and regulatory bodies.

Scenario 11: A Tenant Filing a Complaint Against a Landlord

Suppose a tenant has repeatedly informed a landlord about a leaking ceiling, but no repairs have been arranged.

The tenant could write:

In this example, complaint is the correct noun because the tenant is submitting a formal grievance.

The tenant could also write, “I am writing to complain about the unresolved leak.” This is grammatically correct, but the version using submit a formal complaint explicitly identifies the communication as a formal grievance.

Scenario 12: Complaining to a Bank About an Incorrect Charge

Imagine that a bank customer notices a transaction they do not recognise.

The customer might write:

The verb complain is appropriate because the sentence describes the purpose of the customer’s action.

Alternatively:

“I would like to submit a complaint regarding an unauthorised charge on my account.”

Both sentences are correct. The best choice depends on the style and purpose of the correspondence.

For suspected fraud, the customer should also contact the bank promptly through its official security or dispute-reporting process rather than relying solely on a general complaint email.

Read More: Tear vs Tare: When To Use Each Word Correctly

Common Mistakes When Using Complaint and Complain

Even when people understand the meanings of these words, they sometimes use them incorrectly in sentences. The following mistakes are especially common among English learners.

Mistake 1: Using “Complaint” Instead of “Complain”

Incorrect: “I want to complaint about the poor service.”
Correct: “I want to complain about the poor service.”

Why? The phrase want to must be followed by the base form of a verb. Since complain is the verb, it is the correct choice.

You can also write:

“I want to make a complaint about the poor service.”

In this version, make is the verb and complaint is the noun.

Mistake 2: Using “Complain” Instead of “Complaint”

Incorrect: “I have a complain about the delivery.”
Correct: “I have a complaint about the delivery.”

Why? The phrase I have a requires a noun in this sentence. Complaint is the noun that identifies the problem.

Mistake 3: Forgetting the Article “A”

Incorrect: “She submitted complaint against the company.”
Correct: “She submitted a complaint against the company.”

Why? Complaint is a singular countable noun, so it generally needs a determiner in this construction.

You could also say, “She submitted the complaint against the company,” if the specific complaint is already known.

Mistake 4: Using the Wrong Verb Form

Incorrect: “He complain about the food every day.”
Correct: “He complains about the food every day.”

Why? In the simple present tense, a third-person singular subject such as he, she, or it requires the verb ending -s.

Mistake 5: Using the Wrong Form After “To”

Incorrect: “I want to complained to the manager.”
Correct: “I want to complain to the manager.”

Why? When to marks an infinitive, it is followed by the base form of the verb.

The same rule applies to sentences such as:

• “She wants to complain.”
• “They plan to complain.”
• “We need to complain about the delay.”

Mistake 6: Confusing “Complaint” with “Complaints”

Incorrect: “The company received many complaint.”
Correct: “The company received many complaints.”

Why? The word many is followed by a plural countable noun. The plural of complaint is complaints.

Mistake 7: Using “Complaint” as a Verb

Incorrect: “I complained a complaint to the manager.”
Better: “I made a complaint to the manager.”

Also correct: “I complained to the manager.”

Why? English does not normally use complaint as a verb. You make or submit a complaint, or you complain.

Mistake 8: Choosing an Incorrect Preposition

Incorrect: “I complained the manager about the issue.”
Correct: “I complained to the manager about the issue.”

Why? Use to to identify the person receiving the complaint and about to identify the subject of dissatisfaction.

Is “Complaint” More Formal Than “Complain”?

In many situations, complaint sounds more formal because it is frequently used in official documents and professional correspondence. However, this does not mean that complain is informal or unsuitable for professional use.

Compare these examples:

• “I would like to complain about the service.”
• “I would like to submit a formal complaint about the service.”

Both are appropriate in a professional context. The second sounds more explicitly formal because it identifies the communication as a formal submission.

Similarly:

• “The customer complained about the delay.”
• “The company received a complaint about the delay.”

Neither sentence is inherently more polite than the other. The difference is primarily grammatical and relates to what the sentence emphasises.

If your goal is to sound polite and professional, you can also use expressions such as:

• I would like to raise a concern about…
• I would appreciate your assistance with…
• I am writing to report an issue with…
• I would like to request a review of…
• I would be grateful if you could investigate…

These expressions are especially useful when you want to resolve a problem without sounding unnecessarily confrontational.

Is It Correct to Say “I Have a Complaint” or “I Want to Complain”?

Both expressions are grammatically correct, but they communicate the idea through different grammatical structures.

“I have a complaint” identifies a concern that the speaker wishes to raise.

“I want to complain” expresses the speaker’s intention to take the action of expressing dissatisfaction.

Consider the following examples:

• “I have a complaint about my hotel room.” This identifies the concern.
• “I want to complain about my hotel room.” This expresses an intention to voice dissatisfaction.
• “I made a complaint about my hotel room.” This reports that a complaint was made.
• “I complained about my hotel room.” This reports the action of expressing dissatisfaction.

These sentences may refer to the same situation, but they emphasise different aspects of it.

In everyday conversation, people often use these expressions interchangeably in terms of their overall message. Nevertheless, their grammatical structures cannot be exchanged without changing the sentence.

Read More: Less Than or Less Then: Which Is Correct? Examples And Easy Grammar Guide

British English vs American English: Complaint and Complain

The words complaint and complain are used in both British and American English with the same basic meanings and grammatical roles.

There is no significant difference in their spelling or core usage between the two varieties.

However, some related expressions vary in frequency or preference.

For example:

• Lodge a complaint is common in British English and is also used in other English-speaking regions.
• File a complaint is particularly familiar in American English, although it is not exclusive to the United States.
• Make a complaint is widely understood and used internationally.
• Submit a complaint is common in formal and administrative contexts.

For instance, a British customer might say, “I would like to lodge a complaint about the service,” while an American customer might say, “I would like to file a complaint about the service.”

Both sentences are correct.

The choice often depends on regional habits, institutional procedures, and personal preference rather than a strict grammatical rule.

Each correction illustrates a different rule: verb form, noun selection, subject-verb agreement, pluralisation, or preposition use.

A Quick Reference Guide for Everyday Use

Use the following examples as a quick reminder when writing or speaking English.

What you want to say	Correct expression
Express dissatisfaction	Complain
Identify an issue formally	A complaint
Submit an official grievance	File a complaint
Tell someone about a problem	Complain to someone
Identify the reason for dissatisfaction	Complain about something
Describe a symptom	Complain of pain
Report several grievances	Complaints
Describe repeated dissatisfaction	Keep complaining
Refer to a grievance already reported	The complaint
Describe an intention to express dissatisfaction	Want to complain

Remember that the surrounding words often help you identify which form is needed.

For example, make, file, submit, and receive commonly take the noun complaint. By contrast, want to, need to, will, may, and should are typically followed by the base verb complain when used in constructions expressing intention, necessity, or possibility.

Examples:

• “You should complain if the product is defective.”
• “You should submit a complaint if the company does not resolve the issue.”
• “The manager received a complaint yesterday.”
• “The manager will complain if the report is late.”

These patterns are not an exhaustive list of every possible construction, but they provide a useful foundation for everyday English.

Conclusion

The difference between complaint and complain is simple: complaint is a noun, referring to an expression of dissatisfaction, while complain is a verb, describing the action of expressing dissatisfaction. For example, “I submitted a complaint about the poor service” and “I complained about the poor service” are both correct, but they use the words differently.

To use these words correctly, remember common expressions such as make a complaint, file a complaint, complain about something, and complain to someone. Whether you are writing a professional email, reporting a problem, or speaking in everyday situations, choosing the correct word and maintaining a polite tone will help you communicate clearly and confidently.