B2 Grammar Tenses

The Future Perfect Continuous

The future perfect continuous looks forward to a point in the future and emphasises how long an activity will have been going on by then: By June, I will have been working here for ten years.

The future perfect continuous (also called the future perfect progressive) is the most complex of the future tenses, but its meaning is precise and useful. It projects forward to a specific future point and looks back from there at an activity in progress, stressing its duration. We form it with will have been plus the -ing form of the verb.

It answers the question How long will this have been happening by [a future time]? For example: By the time the train arrives, I will have been waiting for two hours. The waiting continues right up to that future moment, and the emphasis is on the length of time, not on completion.

Form of the Future Perfect Continuous

The structure never changes with the subject: will have been + verb-ing for everyone.

Type Structure Example
Affirmative subject + will have been + -ing She will have been studying.
Negative subject + will not have been + -ing They won't have been waiting long.
Question will + subject + have been + -ing How long will you have been driving?

When We Use It

Use Example
Duration up to a future point By 2030 we will have been living here for 20 years.
Explaining a future cause She'll be tired because she'll have been travelling all day.

Time markers: This tense almost always appears with a future time point and a duration. Use by or by the time for the endpoint, and for for the length: By next month, I will have been training for a year.

Future Perfect Continuous vs Future Perfect Simple

Like other perfect pairs, the difference is duration vs completion. The continuous focuses on the ongoing activity and how long it lasts; the simple focuses on the result that will be finished.

Continuous (duration) Simple (completion/result)
By 5 p.m. I will have been writing for six hours. By 5 p.m. I will have written the report.
She will have been teaching for 30 years. She will have taught 5,000 students.

Use the simple when you mention the amount achieved (the report, 5,000 students) and the continuous when you emphasise how long the activity will have been going on.

Stative Verbs

As with all continuous tenses, do not use stative verbs such as know, own, believe or understand. Use the future perfect simple instead: By Friday I will have known her for a year, not will have been knowing.

Common Mistakes

Practice Exercises

Grammar Quiz

Choose between the future perfect continuous and simple.

Cloze Dropdown

Select the right form after by and by the time.

Complete the Sentence

Type will have been + -ing in each gap.

Matching Pairs

Match future activities with their durations.

Unjumble

Reorder words into future perfect continuous sentences.

Flash Cards

Drill time markers and verb forms for this tense.

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Explore related grammar topics:

All Grammar Topics Future Perfect Future Tenses Future Continuous Present Perfect Continuous

Frequently Asked Questions

What is the future perfect continuous?
It is a tense that projects forward to a point in the future and looks back at an activity in progress, emphasising its duration: By June, I will have been working here for ten years. We form it with will have been + the -ing form of the verb.
How do I form the future perfect continuous?
Use will have been + verb-ing for every subject: She will have been studying; They will have been waiting. For negatives add not (won't have been); for questions invert will: How long will you have been driving?
When do I use the future perfect continuous?
Use it to stress how long an activity will have continued up to a specific future point: By 2030 we will have been living here for 20 years. It can also explain a future situation: She'll be tired because she'll have been travelling all day.
What is the difference between the future perfect continuous and the future perfect simple?
The continuous emphasises duration: By 5 p.m. I will have been writing for six hours. The simple emphasises completion or result: By 5 p.m. I will have written the report. Use the simple when you state the amount achieved, the continuous when you stress how long the activity lasts.
What time expressions go with this tense?
It pairs a future endpoint with a duration. Use by or by the time for the endpoint and for for the length: By next month, I will have been training for a year. Without a duration, the tense usually sounds incomplete.
Why don't I use 'will' after 'by the time'?
Time clauses introduced by by the time, when or before take the present simple, not will: By the time the train arrives, I will have been waiting for two hours. The main clause carries the future form; the time clause stays in the present.
Can I use stative verbs in the future perfect continuous?
No. Stative verbs such as know, own, believe and understand are not used in continuous forms. Use the future perfect simple instead: By Friday I will have known her for a year, not will have been knowing.
How do I make the future perfect continuous negative?
Put not after will: They will not have been waiting long, usually contracted to won't have been. The negative is fairly rare, but it works the same way as the affirmative, just with not added.
Is the future perfect continuous common in everyday English?
It is one of the rarer tenses and appears mostly in careful, formal or planning contexts where duration up to a future point matters. In casual speech, people often simplify it to the future continuous or future perfect. Still, recognising and using it correctly marks advanced, B2-to-C1 control.
Can I contract 'will have been'?
Yes. In speech and informal writing, will contracts to 'll: I'll have been working. The negative will not becomes won't: won't have been working. The have been part is not contracted in this tense.