Consequently vs That's why

When to use each in English, with meaning, register, and examples.

Consequently

Top 3,000 (common)B2adverb

That's why

Top 1,000 (very common)
Most common: That's why
 ConsequentlyThat's why
Pronunciation🇬🇧 /["/ˈkɒnsɪkwəntli/"]/🇺🇸 /["/ˈkɑːnsɪkwentli/"]/🇬🇧 //ðæts waɪ//🇺🇸 //ðæts waɪ//
MeaningAs a result or effect of something.This is the reason.
ExampleThis poses a threat to agriculture and the food chain, and consequently to human health.The project was delayed. That's why we need an extension.
RegisterNeutralNeutral
How commonTop 3,000 (common)Top 1,000 (very common)
CEFR levelB2-
Part of speechadverb
Collocationsconsequently, the outcome, consequently, we decided, used consequently in a sentence, consequently, it appears, the plan failed; consequentlythat's why I, that's why we, that's why she, that's why they, that's why he
Antonymsinconsequently, independently, unrelatedly-
Common mistakesUsing 'consequently' in informal spoken English too often., Confusing 'consequently' with 'consequent' — the former is an adverb, the latter is an adjective., Placing 'consequently' at the beginning of a sentence without a clear prior context.'That's why' is sometimes confused with 'that's because', which has a slightly different use., Learners often forget to follow 'that's why' with a clear explanation., Some may use 'that's why' in overly formal contexts, where a more precise term is needed.
Usage notesUse 'consequently' to show a direct result of something previously mentioned. It's suitable for writing and formal speech, but less common in everyday conversations.Use 'that's why' to explain or justify a statement. It's suitable for conversation and informal writing, but may be less formal in essays.

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That's why

Frequently asked questions: Consequently vs That's why

What's the difference between Consequently and That's why?

Consequently: As a result or effect of something. That's why: This is the reason.

Which is more common: Consequently and That's why?

That's why is the most common in everyday English.

Can you show an example of each?

Consequently: This poses a threat to agriculture and the food chain, and consequently to human health. That's why: The project was delayed. That's why we need an extension.

Can I use Consequently and That's why interchangeably?

Not always. Consequently and That's why are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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