My Fed Tax return is accepted. I would like to receive some of the refund through series I savings bond. Should I file an amendment? If yes, are there any penalties.

too late. the 8888 had to be filed with the return.

Thanks!

However, if you have not yet purchased the annual maximum amount of I Bonds, you can do so directly on the Treasury Direct website (with your own funds).  But you may want to wait until May 1, since the rates are expected to go up substantially.

 Rising inflation may increase yearly rates for I bonds. Here’s what to know – Market Trading Essentials

Thank you, but I have already purchased.