How much hesitation is still acceptable at Band 7?

The Band 7 wording allows "some hesitation, repetition and/or self-correction" as long as it does not affect coherence, and it adds that such hesitation often occurs mid-sentence and can indicate problems with accessing language. So the amount is less important than the effect: hesitation that leaves the thread intact is compatible with Band 7, while hesitation that forces the listener to reconstruct the point is not. Band 8 narrows the same allowance to hesitation that is usually content-related, and Band 9 to hesitation used only to prepare the next idea.

IELTS Speaking Band Descriptors: What Fluency and Coherence Rewards →