Talking About the Future: Going To and Will
When to use 'going to' and when to use 'will' — the difference is about planning, not about time.
English has no single future tense. The two forms you need first are going to and will, and choosing between them is about how you decided, not about how far away the event is.
Going to: plans and evidence
Use going to for decisions made before the moment of speaking, and for predictions based on something you can see.
- I'm going to study medicine. (decided already)
- We're going to visit my parents on Sunday. (arranged)
- Look at those clouds — it's going to rain. (evidence right now)
Form: am / is / are + going to + base verb.
Will: decisions made now, and opinions
Use will for decisions made at the moment of speaking, offers, promises, and predictions based on opinion.
- The phone's ringing. I'll get it. (decided this second)
- I'll help you with that. (offer)
- I think she'll like it. (opinion)
Form: will + base verb, for every subject. Negative: won't.
The classic comparison
A: We need more milk.
B: OK, I'll buy some. (deciding now)
A: Why are you taking the car?
B: I'm going to buy milk. (already planned)
The test question — did you know this before you opened your mouth? If yes, going to. If you are deciding as you speak, will.
Present continuous for arrangements
For fixed arrangements with a time and place, English often uses the present continuous:
- I'm meeting Anna at six.
- We're flying to Rome on Tuesday.
This is very common and sounds natural for diary events.
And present simple for timetables
Public schedules — trains, flights, cinema times, term dates — use the present simple, even about the future.
- The train leaves at 6:40.
- The film starts at eight.
The difference: I'm meeting Anna at six is my arrangement; the train leaves at six is somebody's published timetable.
Two more jobs for will
Won't = refusal. With objects it means "it refuses to work":
- The car won't start.
- She won't listen to me.
Shall for offers and suggestions, with I and we only. It survives in questions even though it has almost vanished elsewhere:
- Shall I open the window? (offer)
- Shall we go? (suggestion)
No "will" after when, if, as soon as
This is the mistake that survives longest. After these time and condition words, English uses the present form even though the meaning is future.
- ❌ I'll call you when I will arrive.
- ✅ I'll call you when I arrive.
- ✅ If it rains, we'll stay in.
- ✅ As soon as she gets here, we'll start.
The will still appears — but only in the other half of the sentence.
Quick guide
| Situation | Use |
|---|---|
| Already decided | going to |
| Deciding right now | will |
| Offer or promise | will |
| Evidence you can see | going to |
| Fixed arrangement | present continuous |
| Published timetable | present simple |
| After when / if / as soon as | present simple |
Making plans on the phone
A: What are you doing on Saturday?
B: We're going to paint the kitchen. Why?
A: I was going to ask you to lunch. I'll call you next week instead.
B: Do — I'll be free once the kitchen's finished. The shop opens at nine, so we'll start early.
Are you doing is the arrangement, going to paint is the plan, I'll call is decided on the spot, and opens is the shop's timetable.
Try it yourself
The quiz below tests the decision-timing difference, which is what actually separates the two.