English

What is a thesis statement, and how do you write a good one?

Quick answer

A thesis statement is one or two sentences, usually at the end of an essay's introduction, that state the main claim the whole essay will prove, often with the reasons why.

Ages 12–18Secondary

In one sentence

A thesis statement is the sentence (or two) that tells the reader exactly what your essay is going to argue or show, and usually why.

Explained

Think of an essay as a case in court. The thesis statement is your promise to the judge: this is what I am going to prove. Every paragraph after it is evidence for that promise. Without a thesis, an essay is just a collection of thoughts about a topic; with one, it has a direction.

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Plan the claim, write it in one sentence, then check every paragraph against it.

The most important difference to understand is between a topic and a thesis. A topic is what you are writing about: school uniforms. A thesis is what you claim about it: School uniforms should be optional, because they limit self-expression and cost families money. A topic cannot be wrong; a thesis can be argued against, and that is exactly why it is worth writing an essay about.

A strong thesis statement has three qualities:

It makes a claim. It is an opinion, an interpretation or a judgement, not a plain fact. Learn to tell a fact from an opinion and you are halfway there.
It is specific. It names exactly what you mean. Social media is bad is vague; Social media apps should not be allowed for under-13s, because they disrupt sleep and expose children to strangers is precise.
It can be proved in the space you have. A 600-word essay cannot prove War has shaped all of human history.

In most school essays the thesis comes at the end of the introduction. The opening sentences catch the reader's interest and give background; the thesis then states your position, and the body paragraphs prove it one reason at a time. Each body paragraph starts with a topic sentence that links back to the thesis (see paragraphs).

There are three main kinds of thesis, and teachers often name them:

Argumentative (persuasive) thesis: takes a side on a debatable question. Our school should replace plastic cups with refillable bottles. This is the heart of persuasive writing.
Analytical thesis: breaks a text, speech or problem into parts and claims something about how or why it works. It is used in literary analysis and rhetorical analysis essays. In “Of Mice and Men”, Steinbeck uses George and Lennie's dream of owning a farm to show how loneliness drives people to hope for things they may never reach.
Expository (informative) thesis: explains a topic without taking a side, but still tells the reader exactly what the essay will cover. Volcanoes form in three main settings: where tectonic plates pull apart, where they collide, and over hot spots.

A useful pattern for beginners is topic + claim + reasons: [Topic] [should / is / shows] [claim] because [reason 1] and [reason 2]. More experienced writers add a concession with although: Although uniforms can reduce teasing about clothes, they should be optional, because… This shows you have thought about the other side.

Examples

Weak thesis	What is wrong	Stronger thesis
This essay is about homework.	Announces the topic, makes no claim.	Primary pupils should have no more than 20 minutes of homework a night, because longer sessions eat into sleep and play.
Phones are used by many teenagers.	A fact nobody disputes.	Schools should collect phones at the start of the day, because constant notifications make it harder to concentrate in lessons.
Pollution is bad.	Far too vague.	Our town should ban cars from the high street on Saturdays to cut noise and fumes where people shop.
Should we have a four-day school week?	A question, not an answer.	A four-day school week would hurt younger pupils, because working parents would need childcare on the fifth day.
Shakespeare is a great writer.	Too broad and unprovable in one essay.	In “Macbeth”, Shakespeare uses images of blood to show that guilt cannot be washed away.

A rhetorical analysis thesis names the speaker, the purpose and the techniques: In his “I Have a Dream” speech, Martin Luther King Jr. uses repetition, references to the Bible and to America's founding documents to persuade his audience that equal rights cannot wait. The techniques themselves are explained under rhetorical devices.

Common mistakes

Announcing instead of arguing. In this essay I will talk about uniforms tells the reader nothing. Fix: delete the announcement and state your claim directly.
Stating a fact. The Second World War ended in 1945 cannot be argued. Fix: ask so what? and claim something about the fact, such as why it happened or what it changed.
Being too broad. Technology has changed the world would need a library. Fix: narrow it to one place, group, time or effect.
Writing a question. A question can open an introduction, but the thesis is your answer to it.
Drifting away from the thesis. If your essay ends up proving something different, revise the thesis at the end so it matches what you actually argued.

Step by step

Turn the task into a questionDiscuss school uniforms becomes Should school uniforms be compulsory?
Answer it in one sentenceThis is your working thesis: School uniforms should be optional.
Add your reasonsUse because: …because they limit self-expression and cost families money. Each reason becomes one body paragraph.
Sharpen the wordsReplace vague words (good, bad, things, society, a lot) with exact ones.
Test itCould someone disagree? Can you prove it in the length you have? Does every paragraph support it?
Place and revisePut it at the end of your introduction, write the essay, then reread the thesis and adjust it to match.

Practice questions

Thesis or not? Fix it

Try each one, then check your answer.

Thesis or not? “This essay is about homework.”
Show answer
It only names the topic: not a thesis.
Thesis or not? “Primary pupils should have no more than 20 minutes of homework a night, because longer sessions eat into sleep and play.”
Show answer
A clear, arguable claim with reasons: a thesis.
Thesis or not? “The Second World War ended in 1945.”
Show answer
A fact nobody disputes: not a thesis.
Thesis or not? “Should schools ban phones?”
Show answer
A question: not a thesis. Answering it (for example Schools should ban phones in lessons because…) would make one.
Argumentative, analytical or expository? “Schools should start at 9:30, because teenagers concentrate better later in the morning.”
Show answer
It takes a side: argumentative.
Argumentative, analytical or expository? “Volcanoes form in three main settings: where plates pull apart, where they collide, and over hot spots.”
Show answer
It explains without taking a side: expository.
Argumentative, analytical or expository? “In “Cinderella”, the glass slipper turns a small object into proof of who Cinderella really is.”
Show answer
It interprets how a story works: analytical.
Topic sentence or thesis? “First, uniforms save families money.”
Show answer
It gives one supporting reason for one paragraph: a topic sentence.
Which is more specific? A: “Recycling is important.” B: “Our town should collect food waste separately, because it cuts landfill and can be turned into compost.”
Show answer
B: it says exactly what should happen and why.
Is this too broad for a 500-word essay? “The history of the world has been shaped by war.”
Show answer
Yes, too broad. Narrow it, for example: The invention of the printing press helped spread new ideas across Europe in the 1500s.
Fix the announcement: “In this essay I will discuss school uniforms.”
Show answer
State a claim instead, for example: School uniforms should be optional, because they limit self-expression and cost families money.
Fix the vague thesis: “Social media is bad.”
Show answer
Make it specific, for example: Social media apps should not be allowed for under-13s, because they disrupt sleep and expose children to strangers.
Add a concession with although to: “Zoos should be closed.”
Show answer
For example: Although zoos help some endangered species, most should be replaced by wildlife reserves, because large animals need far more space than a zoo can give.
Find the thesis: “Every year, thousands of trees are planted in parks. Yet many die within a few years. Our council should spend less on planting new trees and more on caring for young ones.”
Show answer
The claim at the end: Our council should spend less on planting new trees and more on caring for young ones.

Questions people ask

What is a thesis statement in an essay?

It is the sentence, or pair of sentences, that states the main claim of the whole essay. Everything else in the essay exists to explain or prove it.

What is an analytical thesis statement?

It is a thesis that makes a claim about how or why something works, such as a poem, a speech or a historical event. Instead of saying a book is good, it says what the author does and what that achieves: Steinbeck uses the farm dream to show…

What is the difference between a thesis statement and a topic sentence?

The thesis is the main claim of the whole essay and comes in the introduction. A topic sentence opens one body paragraph and states the single point that paragraph will prove. All the topic sentences together support the thesis.

How many thesis statements should an essay have?

One. It can be one or two sentences long, but there is only one main claim. If you have two separate claims, you either have two essays or need a broader claim that links them.

How do you start a thesis statement?

Start with your subject and your claim, not with In this essay I will. Common openings are the topic itself (School uniforms should…), a concession (Although…) or, for analysis, the author and text (In “Macbeth”, Shakespeare…).

Can a thesis statement be a question?

No. A question can hook the reader at the start of an introduction, but the thesis is the answer you are going to defend.

What is an expository thesis statement?

It is the thesis of an informative essay. It does not take a side, but it tells the reader exactly what will be explained and often in what order, like a short map of the essay.

Should I use a thesis statement generator?

A template can show you the shape (topic + claim + reasons), but it cannot know your evidence or your opinion. Write your own answer to the question first, then use the step-by-step test above to sharpen it.

Quick quiz

Thesis statements

Check what you know with 5 quick questions.

Question 1 of 5

Which sentence is a thesis statement?

Practise it

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Practise writing thesis statements

Ready for literature essays? Try writing an analytical thesis.

Practise it step by step in a full course: Grade 10 English