How to write an essay introduction
A first paragraph has one minute to earn a reader's attention and tell them where the essay is going. This guide breaks the introduction into three jobs, shows the openings that quietly sink an essay, and builds two worked examples so you can copy the shape.
An introduction does three things in a small space. It catches interest, it gives the reader enough context to follow you, and it states the claim the rest of the essay will defend. Most weak introductions fail because they try to do only one of those three, or because they pad the opening with background that belongs nowhere. Once you can name the three jobs, you can check any draft introduction in seconds: does it hook, does it orient, does it commit?
Job one: the hook
The hook is the first sentence or two, and its only task is to make a reader want the next line. In academic writing the hook is restrained. It is a precise fact, a brief contradiction, or a focused question, not a fireworks display. "Every year, UK households throw away around 6.4 million tonnes of food, and most of it was still edible when it hit the bin." That opens a food-waste essay with a number a reader did not expect, which is enough.
A question can also work if it is specific. "Why do students who revise harder sometimes score worse?" is a sharper hook than "Have you ever wondered about studying?" The first promises a puzzle the essay will solve. The second is filler. The test for any hook is simple: would a tired marker reading their fortieth script keep going after this line? If the answer is no, cut it and try again.
Job two: the context
After the hook comes a sentence or two that moves the reader from the broad topic to the narrow question your essay actually answers. This is the bridge. It supplies only the background needed to understand your thesis, nothing more. If your essay argues about grid connection delays in renewable energy, the context names the energy transition and the assumption that cost is the main barrier, so that your thesis can then push back against that assumption.
The common mistake here is starting too wide. "Since the dawn of time, humans have used energy" tells the reader nothing and wastes your best real estate. A useful image is a funnel: begin a little broader than your thesis, then narrow with each sentence until the thesis drops out as the obvious next step. Two or three sentences of context is plenty for a standard essay.
Job three: the thesis
The thesis is the claim your essay will defend, and it usually lands as the last sentence of the introduction. By the time the reader reaches it, the hook has caught them and the context has oriented them, so the claim feels earned rather than dropped in cold. A strong thesis takes a position a reasonable person could dispute and hints at the grounds. "The main barrier to a faster renewable transition in the UK is not technology cost but the slow pace of grid connection approvals" does both.
If you are still shaping the claim itself, work on it separately before you fit it into the paragraph. A vague thesis cannot be rescued by a good hook. Once the claim is solid, the rest of the introduction has something firm to point at.
What to leave out
Several habits weaken introductions, and most students use at least one. The dictionary opener ("The Oxford English Dictionary defines justice as...") is the most common and the easiest to cut, because it tells the reader something they already know. The cosmic opener ("Throughout human history, people have struggled with...") promises a scope no essay can deliver. The throat-clearing opener ("In this essay I will discuss...") announces the work instead of doing it.
Two more to watch. Do not stack your whole body of evidence into the introduction; save the proof for the paragraphs built to carry it. And do not apologise or hedge ("Although I am no expert..."), because it asks the reader to trust you less before you have written a word. Cut these and the introduction gets shorter and stronger at the same time.
A worked argumentative opening
Here is the three-job structure applied to an argumentative essay on phone bans in schools. Read it once, then look at the labels.
In 2024, several English secondary schools banned phones from the gates inward, and early reports claimed calmer corridors within weeks. Supporters treat the policy as settled common sense: remove the distraction and learning improves. The evidence is thinner than the headlines suggest. A blanket phone ban does little for the students who were already focused and removes a tool that struggling readers and anxious pupils quietly rely on, which means the policy trades a visible win for a hidden cost.
The first sentence is the hook, a concrete recent event with a surprising claim attached. The next sentence is the context, naming the popular assumption the essay will challenge. The final sentence is the thesis, taking a contestable position and previewing two grounds, the limited benefit and the hidden cost. Three sentences, three jobs.
A worked expository opening
Expository essays explain rather than argue, so the thesis states what the essay will show rather than a position to defend. The three jobs still apply.
A loaf of supermarket bread can list more than twenty ingredients, yet bread needs only four. The gap between those two numbers is the story of the Chorleywood process, a method developed in 1961 that let British bakeries produce a soft, uniform loaf in a fraction of the old time. Understanding how Chorleywood works, and what it added beyond flour, water, yeast, and salt, explains why modern bread keeps for a week and why some eaters find it harder to digest.
Again the first sentence hooks with an unexpected contrast. The middle sentence supplies the context, naming the process and its date so the reader is oriented. The closing sentence is the expository thesis: it tells the reader exactly what the essay will explain, without pretending to argue a side. If you need to turn a thesis like this into a full plan, the Phrasit essay outliner expands a claim and a few supporting points into a working outline.
Revising the introduction last
The introduction you write first is a guess, and that is fine. After the body is done you will know what the essay actually argued, which is often a little different from what you planned. Come back and rewrite the thesis to match where the evidence led, then check that the hook still fits and the context still points the right way. A reliable final check: read only your first paragraph and your last paragraph back to back. If they agree on what the essay claims, the introduction is doing its job.
What to do next
Draft your three sentences, then turn the thesis into a plan with the essay outliner. Once the full draft is down, check the opening reads at the right level with the reading level analyzer, and keep the introduction near ten percent of the total with the word counter.