Use going to for plans you made before speaking and for predictions based on what you can see now. Use will for decisions made at the moment of speaking, offers, promises, and predictions based on opinion. In many sentences both are possible, and the difference is small.
The two forms
Will is a . It does not change for the person, and it is followed by the base form of the verb: I will go, she will go, they will go. The short form is 'll, and the negative is will not or won't.
Going to is be + going + to + base verb: I am going to study, she is going to study, they are going to study. In speech, going to often sounds like gonna, but write going to in IELTS Writing and use the clear full form when you want to sound careful.
Always use the base verb after both forms. Do not say I will to go or She is going to studies.
- I will call you later. · I am going to call my tutor tonight.
- She won't be late. · She isn't going to be late.
Use going to for plans and for evidence
Going to has two main jobs. The first is a plan or intention you decided before you speak. If you have already bought tickets or made a decision, going to shows that the decision is old: We are going to visit my grandparents in Wales next month.
The second job is a prediction based on evidence you can see or know now. If you see black clouds, you say It is going to rain. If a company's sales are falling, you say The company is going to lose money. The present situation tells you what happens next.
- A plan: I am going to apply for a scholarship this autumn.
- An intention: She is going to become a nurse.
- Evidence now: Look at the traffic. We are going to be late.
Use will for decisions, offers, promises and opinions
Will is the right choice when you decide at the moment of speaking. If your phone rings while you are busy, you say I'll answer it. The decision is new, so will is the natural choice.
Will is also natural for offers (I'll carry that bag for you), promises (I won't tell anyone), and refusals (The company won't change the rules). It is also the usual form for predictions based on your opinion or general knowledge, often with phrases such as I think, I believe, probably, and I'm sure: I think public transport will become cheaper.
In formal writing, will is the normal form for facts about the future: The conference will begin at nine o'clock.
When both are possible
Many predictions about the future can use either form. Technology will change how people work, and Technology is going to change how people work are both correct. In these cases, going to sounds a little more informal and personal, while will sounds more general and formal.
In IELTS Writing Task 2, use will and phrases such as is likely to and may when you discuss the future. They sound more careful and academic than going to, and they are good for talking about predictions. In IELTS Speaking, going to is natural for your own plans: I'm going to study engineering.
Questions and negatives
Questions with will put will before the subject: Will the new library open soon? Questions with going to use the verb be first: Is the new library going to open soon? In short answers, repeat the helper only: Will it open soon? Yes, it will. Is it going to open soon? No, it isn't.
For negatives, use will not or won't, and am not, is not or are not going to. People often shorten these in speech. In Writing Task 2, keep the full form: Governments will not solve the problem alone. This small choice makes your style more formal.
Common mistakes
Using will for a plan you made long ago can sound as if you have only just decided. If a friend asks about next weekend and you booked a trip last month, I'm going to visit my cousin is more natural than I will visit my cousin. A second error is adding to after will, as in I will to go.
A third mistake is using will after if or when for a future event. Say If it rains tomorrow, we will stay in, not If it will rain tomorrow. The if clause uses the present simple, even when the meaning is about the future.
Finally, do not use the present continuous for every future. It is good for fixed arrangements (I'm meeting my tutor at four), but it is not a general replacement for will or going to.
Who finds this hard?
- Spanish speakers: Spanish has ir a plus an and a future tense, so the two English forms feel familiar, but the choice between them does not match the Spanish one exactly.
- Italian speakers: Italian uses a simple future for many plans and predictions, so learners often use will where going to is more natural.
- Chinese speakers: Chinese verbs have no future ending, so learners must remember to add will or going to and to use the base verb after it.
IELTS tip
In Writing Task 2, predictions with will, is likely to and may sound careful and academic, so use them to discuss future effects. In Speaking Part 2 and Part 3, going to is a natural way to talk about your own plans, such as After the test I'm going to look for a part-time job.
Frequently asked questions
Is there a real difference between will and going to?
Yes, in some situations. Going to shows a plan made before speaking or evidence now, and will shows a new decision, an offer, a promise or an opinion. In many predictions, both are fine.
Which is better for IELTS Writing?
Will, is likely to and may are natural choices in academic writing. Going to is acceptable but sounds more personal and informal.
Can I use the present continuous for the future?
Yes, for fixed arrangements, such as I'm seeing the dentist on Friday. It is not a replacement for will in general predictions.
Do I say gonna in the speaking test?
Gonna is natural in fast, relaxed speech, but going to is always safe. Do not write gonna in an essay.
Sources
- Swan, M. (2016). Practical English Usage (4th ed.). Oxford University Press.
- Biber, D., Johansson, S., Leech, G., Conrad, S. and Finegan, E. (1999). Longman Grammar of Spoken and Written English. Longman.