I only rebonded it the one time.. And I absolutely regretted it.. I never really like straight hair on me. Anyways, what do you mean how long? Like the actual process? Then I think it was for at least 30 minutes to 2 hours.. Sorry, I didn't pay attention. It was my mom who decided it. While I was trying to grow it out, I tried the cg method and no poo to try and make it curl again, and it did help. But since I've been swimming recently I've been using shampoo again, the exact and only product I pretty much used before rebonding my hair.. So I'm still not sure.