Do you put a comma before or after therefore?

Therefore often needs a comma after it.

In American English, if “therefore” is used at the beginning of a sentence or independent clause, it needs a comma after it.

Therefore at the beginning of a sentence example
The office is closed next week. Therefore, there will be some delay in replying to emails.

Don’t put a comma before or after “and therefore” if it is part of a compound predicate (i.e., the two verbs are “sharing” the same subject).

Therefore in a compound predicate example
The product was damaged and therefore reduced in price. [Verbs sharing the subject, “the product”]

If you use “therefore” midsentence to deliberately “interrupt” the flow of a sentence for emphasis, it needs commas before and after it. But bear in mind that this will emphasize the information that comes before it.

Therefore used for emphasis example
The office is closed next week. Calls, therefore, will not be answered. [“Calls” is emphasized, e.g., to communicate that emails will be answered]

Note that therefore and therefor are two different words. “Therefor” doesn’t generally need commas before or after it.

Use QuillBot’s free Grammar Checker to help you punctuate “therefore” correctly in your writing.

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