by then

USAGE SUMMARY

'by then' is correct and usable in written English.
By then can be used to say that something will have already happened by a certain time in the future. For example: "I'll have finished my project by then."

✓ Grammatically correct

News & Media

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

By then, the….

The New Yorker

By then, L.S.U.

The New York Times

"I'll be eighty by then".

The New Yorker

I'll be eighteen by then".

The New Yorker

By then, it was late.

The New York Times

Arsenal by then was troubled.

The New York Times - Sports

By then, he had company.

The New York Times

By then Madrid had gone.

The Guardian - Sport

By then I was 35.

The New York Times

(Cesare was dead by then).

The New Yorker

By then he was married.

Encyclopedia Britannica

Expert writing Tips

Best practice

Use "by then" to clearly establish a deadline or a point in time before which an action must be completed or a state achieved. This adds clarity and helps the reader understand the sequence of events.

Common error

Avoid using simple future tense after "by then". It's more appropriate to use the future perfect tense (will have + past participle) to indicate that an action will be completed before the specified time.

Linguistic Context

The phrase "by then" functions as an adverbial of time, modifying a verb or clause to indicate when an action or state will have been completed or reached. Ludwig AI confirms its correctness and usability in written English.

Expression frequency: Very common

Frequent in

News & Media

85%

Encyclopedias

5%

Science

3%

Less common in

Formal & Business

2%

Wiki

3%

Social Media

2%

Ludwig's WRAP-UP

In summary, "by then" is a versatile adverbial phrase used to specify a future point in time by which something will have occurred. As Ludwig AI confirms, its grammatical status is correct, and its frequency of use is very common, particularly in the news and media. Remember to use the future perfect tense when constructing sentences with "by then" to avoid common tense errors. Alternatives include "subsequently" and "thereafter" for more formal contexts. Overall, "by then" is a clear and effective way to establish temporal relationships in your writing.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

at that point

Focuses on a specific moment in time, similar to "by then" but less about a duration leading up to it.

subsequently

Highlights the sequence of events, placing more emphasis on what follows.

afterward

A more general term for what happens following a specific event, less precise than "by then".

thereafter

Implies a formal or legal context, referring to events that occur after a specific time.

at a later time

More descriptive and less concise than "by then", suitable for emphasis.

in that case

Emphasizes a conditional aspect, implying a consequence tied to the time frame.

eventually

Indicates that something will happen at some unspecified time in the future, with no implied deadline.

down the line

Indicates a more distant or undefined future point, lacking the immediacy of "by then".

in the interim

Focuses on the period between two events, rather than the point "by then" references.

in due course

Implies events will happen when appropriate, less specific about timing.

FAQs

How do I use "by then" in a sentence?

"By then" is used to indicate that something will have happened before a specific time in the future. For example, "I will have finished the report by then."

What's a more formal alternative to "by then"?

In formal contexts, you could use phrases like "subsequently" or "thereafter", although these have slightly different nuances.

Is it correct to use "by then" at the beginning of a sentence?

Yes, "by then" can be used at the beginning of a sentence to introduce a condition or event that will be true or completed at a specified future time. For example, "By then, the project will be finished."

Which is correct, "by then" or "than"?

"By then" indicates a point in time, whereas "than" is used for comparisons. They are not interchangeable. The correct usage depends entirely on the intended meaning of the sentence.