CFR /  Title 31  /  Part 359  /  Sec. 359.47 How is payment made for purchases of book-entry Series I

You may only purchase book-entry Series I savings bonds online through your New Treasury Direct account. You may pay for your securities through a debit to your designated account at a United States depository financial institution, or by applying the redemption proceeds of a certificate of indebtedness held in your New Treasury Direct account. [69 FR 50308, Aug. 16, 2004]