Afraid not vs Not really

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

Afraid not

InformalBeyond 10,000 (less common)

Not really

InformalTop 2,000 (common)
Most common: Not really
 Afraid notNot really
Pronunciation🇬🇧 //əˈfreɪd nɒt//🇺🇸 //əˈfreɪd nɑt//🇬🇧 //nɒt ˈrɪəli//🇺🇸 //nɑt ˈrɪəli//
MeaningMeaning you disagree or refuse what was said.Not true or correct.
ExampleCan you help me with my homework?When he said he was an expert, I thought, 'Not really'.
RegisterInformalInformal
How commonBeyond 10,000 (less common)Top 2,000 (common)
Collocationsafraid not, not really, unfortunately notnot really my thing, not really sure, not really interested
Common mistakesConfused with 'I'm afraid' which is a more polite way to decline., Used in overly formal contexts where it sounds inappropriate., Misunderstood as a direct refusal without considering tone.Using it in very formal writing or speeches., Confusing with 'not really' as a definitive answer instead of an expression of doubt.
Usage notesUsed mainly in casual conversation to gently say 'no'. Avoid in formal situations.Used to express disagreement or doubt. Common in casual conversations, but may be too informal for formal settings.

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Afraid not
Not really

Frequently asked questions: Afraid not vs Not really

What's the difference between Afraid not and Not really?

Afraid not: Meaning you disagree or refuse what was said. Not really: Not true or correct.

Which is more common: Afraid not and Not really?

Not really is the most common in everyday English.

Can you show an example of each?

Afraid not: Can you help me with my homework? Not really: When he said he was an expert, I thought, 'Not really'.

Can I use Afraid not and Not really interchangeably?

Not always. Afraid not and Not really 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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