Not now vs Not this time

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

Not now

InformalTop 2,000 (common)

Not this time

Top 2,000 (common)
Most formal: Not this time
 Not nowNot this time
Pronunciation🇬🇧 //nɒt naʊ//🇺🇸 //nɑt naʊ//🇬🇧 //nɒt ðɪs taɪm//🇺🇸 //nɑt ðɪs taɪm//
MeaningSay you don't want to do something at this moment.this time, no.
ExampleCan you help me with this? I need to finish my project.I appreciate the offer, but it's not this time.
RegisterInformalNeutral
How commonTop 2,000 (common)Top 2,000 (common)
Collocationsnot now, please, not now, later, not now, I'm busysay not this time, choose not this time
Antonyms-yes, certainly, this time
Common mistakesUsing it in a formal setting where a more polite refusal is needed., Misunderstanding it as a definitive 'no' instead of a temporary pause., Confusing it with 'not now,' meaning 'never' in some contexts.Using it when it's not a refusal., Confused with 'not this moment' which implies a future possibility.
Usage notesUsed to indicate that the speaker is not ready or willing to engage in something at this time. Best for casual conversations; may seem rude in formal contexts.Used to refuse or deny something in the present context. Appropriate in both casual and formal situations when declining an offer or proposal.

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Not now
Not this time

Frequently asked questions: Not now vs Not this time

What's the difference between Not now and Not this time?

Not now: Say you don't want to do something at this moment. Not this time: this time, no.

Which is more formal: Not now and Not this time?

Not this time is the most formal of these.

Can you show an example of each?

Not now: Can you help me with this? I need to finish my project. Not this time: I appreciate the offer, but it's not this time.

Can I use Not now and Not this time interchangeably?

Not always. Not now and Not this time 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.