So you transferred $600 from a non-chase account to chase. The non-chase account charged you an overdraft fee. Now the $600 is in the account at chase and you want to move it back to the non-chase account. Assuming this is correct then there should be no fees involved, unless you no longer have $600 at chase.

Obviously you have to pay them the $600, and it has basically turned into a loan. This "loan" went into your Chase account - it's the other account that's short. The bank didn't say no you don't have to return the $600 unless you already did when you paid the return fee.

Don't know what you mean by an "external" account. If you're overdrafted, fix it now.

I was transferring money in between accounts.

I overdrafted my external account by 600 dollars.I was transferring money into my chase account. My chase account says the money is available but that can not be true because it is not my money.

My external account charged me an overdraft fee. Which I paid. Im wondering will I have to return the money or will the bank charge a return fee.(I asked my bank and they said no)