Zorg SpaceWhen do I use “will” and when do I use “going to”?
Short answer
Use going to for plans you have already decided (I’m going to study medicine) and for predictions based on what you can see now (Look at those clouds — it’s going to rain). Use will for decisions you make at the moment of speaking (The phone’s ringing — I’ll get it), for offers and promises (I’ll help you), and for predictions based on opinion or belief (I think she’ll win).
For fixed arrangements with a time and other people involved, English often uses the present continuous: I’m meeting Sara at six. In many predictions, both will and going to are correct and the difference is small.
Going to: plans and visible signs
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We’re going to move next year.
a decision made before now
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I’m going to call the bank tomorrow.
a plan
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Careful — that glass is going to fall!
evidence right now
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She’s going to have a baby.
visible, already happening
Will: decisions now, offers, promises, opinions
-
“We’re out of milk.” — “I’ll buy some.”
decided at this moment
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I’ll carry that for you.
offer
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I’ll send it tonight, I promise.
promise
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I think it will be a good year.
opinion about the future
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The meeting will start at 9.
a neutral fact, common in formal or written English
Present continuous: arrangements
When something is arranged — booked, agreed, in the calendar — the present continuous sounds most natural:
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I’m seeing the dentist on Friday.
an appointment
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They’re flying to Seoul next week.
tickets bought
Going to would also be correct here; will would sound odd for a personal arrangement.
Side by side
| Situation | Best choice | Example |
|---|---|---|
| plan decided before | going to | I’m going to learn Korean. |
| decision at this moment | will | Okay, I’ll take the blue one. |
| offer or promise | will | I’ll help you move. |
| prediction from evidence now | going to | He’s going to miss the bus. |
| prediction from opinion | will (or going to) | I think prices will rise. |
| fixed arrangement | present continuous | We’re having dinner with them on Sunday. |
| timetable | present simple | The train leaves at 7:40. |
After “when”, “if”, “as soon as”…
In time clauses and conditions about the future, English uses the present tense, not will:
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I’ll call you when I arrive.
not “when I will arrive”
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If it rains, we’ll stay inside.
not “if it will rain”
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As soon as she finishes, she’ll let us know.
Common mistakes
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Not: I will visit my grandmother tomorrow — I booked the train last week.
Better: I’m going to visit / I’m visiting my grandmother tomorrow.
-
Not: “The phone is ringing.” — “I’m going to answer it.”
Better: “I’ll answer it.”
a decision made right now
-
Not: Look at the sky! It will rain.
Better: Look at the sky! It’s going to rain.
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Not: I’ll call you when I will get home.
Better: I’ll call you when I get home.
-
Not: I will to go to the party.
Better: I will go to the party.
Short forms in speech
In speech, will is usually contracted (I’ll, you’ll, it’ll, won’t) and going to often becomes “gonna”: I’m gonna call her. Write the full forms in formal writing.
In short
- going to: plans already made, predictions from present evidence.
- will: decisions now, offers, promises, opinions, neutral facts.
- present continuous: personal arrangements.
- After when, if, as soon as, use the present tense for the future.
Lessons on this in the library
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