portablity from one branch of a branch to another branch seems to work fine with my SBI account. Heres my scenario: I have a SBI and HDFC savings account. I have registered as third party in each account to transfer between accounts using their IFSC and account number codes. I transfered the SBI account from Bangalore to Nagercoil and SBI retained the number which I had in the Bangalore branch, even though the default starting number for Nagercoil is diferent. Now, from my HDFC account, I transferred Rs.5 to the SBI account using the Bangalore(old) IFSC code. It was successful. This means that I don't have to ask my friends to register my account again with their online accounts.If IFSC is not an issue within the same bank, may be same can be done for interbank.