Future continuous and future perfect in English: will be doing vs will have done
Most learners stop at will and going to and never come back. That is a shame, because the two forms on this page do something neither of those can: they place an action against a point in the future and say whether it is still running or already over. At nine I'll be cooking and by nine I'll have cooked describe the same kitchen at the same time, and mean completely different things to the person deciding when to knock.
The future tense page covers will, going to, the present continuous and the present simple. This one takes the two structures that page only introduced and gives them the space they need.
Future continuous: will be + -ing
The form never changes for the subject: I will be waiting, she will be waiting, they will be waiting. Short form I'll be waiting, negative won't be waiting, question will you be waiting?
It has three jobs.
1. An action in progress at a future moment. You pick a time and say what will be going on around it.
- This time tomorrow I'll be flying to Rome.
- Don't call at eight; we'll be having dinner.
- At four o'clock the children will be walking home.
The moment is a window you look through, not a start or an end. The action began before the window and carries on after it.
2. Something that will happen as a matter of course. No decision, no intention, just the normal run of things.
- I'll be seeing Tom on Thursday anyway, so I'll ask him.
- We'll be passing your street, so we can drop it off.
This is why I'll be seeing him feels neutral while I'll see him can sound like a promise or a threat, depending on the day.
3. Polite questions about other people's plans. This is the use worth stealing straight away.
- Will you be using the car tonight?
- Will you be coming to the meeting?
Will you use the car? and will you come? ask the listener to commit. The continuous version only asks what is already arranged, so it leaves them a way out. English does a lot of its politeness by pretending not to ask.
Future perfect: will have + past participle
Form: will have + the past participle, unchanged for every subject. I will have finished, she will have finished, they will have finished. Short form I'll have finished, negative won't have finished.
It says one thing: this will be complete before that future point.
- By next week I'll have finished the job.
- They'll have left by the time we arrive.
- By the end of the month she'll have worked here for ten years.
Notice that all three name the future point. That is not decoration, it is the condition of use. The future perfect is a deadline tense, and a deadline needs a date. I'll have finished on its own leaves the listener waiting for the rest of the sentence. If you have no future point in mind, you do not want the future perfect; you want plain will: I'll finish it.
The future point can arrive in three ways:
- a time phrase with by: by six, by Christmas, by next spring
- a time clause: by the time you get here, before the shop closes
- a moment already established by the conversation: the train leaves at ten. - Don't worry, we'll have eaten.
By is a deadline, until is a stretch
This pair costs learners more marks than the tenses themselves, and the difference is simple once you see it.
By means at that time or any time earlier. It marks a single deadline, and it goes with finished actions.
Send it to me by Friday. (Thursday is fine. Saturday is not.)
Until means up to that time and no longer. It marks a stretch of time, and it goes with situations that continue.
The shop stays open until nine. (It is open all the way to nine.)
Test yourself with these two: I'll finish it by six (it is done at six at the latest) and I'll work until six (I stop at six). Swap them and both sentences break. The future perfect naturally pairs with by, because both are about a point at which something is already over. Until almost never sits with the future perfect; it belongs with continuous or negative ideas: she won't leave until the job is done.
Future perfect continuous: will have been + -ing
The rare one, worth ten seconds of your time. Will have been + -ing measures how long something has been going on when the future point arrives.
- In June she'll have been working here for a year.
- By the time you get here I'll have been waiting for two hours.
Compare it with the plain future perfect: I'll have written three reports counts the results, I'll have been writing for six hours counts the time. If your sentence contains for plus a length of time, this is usually the form you want.
With time clauses
Both structures spend most of their lives next to a time clause, and that is where learners drop the most obvious point in the whole topic:
You do not put will in the time clause.
- By the time you arrive, I'll have finished. (not you will arrive)
- We'll be eating when she gets here. (not when she will get)
The main clause carries the future form; the clause after when, before, until, as soon as or by the time uses a present tense. This is the same rule that governs if sentences in the conditionals, and it is set out in full on the time clauses page.
Summary table
| Form | Structure | Meaning | Example |
|---|---|---|---|
| Future simple | will + base | a plain future action | I'll call you. |
| Future continuous | will be + -ing | in progress at a future time | At six I'll be driving home. |
| Future perfect | will have + p.p. | finished before a future time | By six I'll have driven home. |
| Future perfect cont. | will have been -ing | how long, measured to a future time | By six I'll have been driving for hours. |
Common mistakes
Ranked by how often learners actually make them.
- Future perfect with no deadline. I will have finished the report leaves the listener hanging. Add the point: I'll have finished the report by Tuesday, or drop back to I'll finish the report.
- Will inside the time clause. By the time I will get there is wrong in every register. Use the present: by the time I get there.
- By where until belongs. I'll stay by six should be I'll stay until six. Staying is a stretch, not a deadline.
- Future continuous for a plan you decided just now. If you are deciding as you speak, use will: the phone's ringing - I'll get it, not I'll be getting it.
- Dropping have or been. I will finished and I'll have working are broken forms. Count the parts: will + have + participle, or will + have + been + -ing.
- Using the future perfect where the present perfect belongs. I will have lived here for ten years said today should be I have lived here for ten years. The future perfect measures to a future point, not to now.
Practice
Choose the best form. Answers are below.
- Don't ring at seven. We
___(eat) at that time. - By the time the film starts, we
___(find) our seats. - This time next year I
___(live) in another city. ___(you / use) the kitchen this evening?- In March she
___(work) here for five years.
Answers: 1. will be eating (in progress at that moment) 2. will have found (finished before the film starts) 3. will be living (in progress across that future time) 4. Will you be using (a polite question about an arrangement) 5. will have been working (how long, measured to a future point; will have worked is also accepted)