31 CFR § 359.16 - When does interest accrue on Series I savings bonds?

---
identifier: "/us/cfr/t31/s359.16"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "31 CFR § 359.16 - When does interest accrue on Series I savings bonds?"
title_number: 31
title_name: "Money and Finance: Treasury"
section_number: "359.16"
section_name: "When does interest accrue on Series I savings bonds?"
chapter_name: "FISCAL SERVICE, DEPARTMENT OF THE TREASURY"
subchapter_number: "A"
subchapter_name: "BUREAU OF THE FISCAL SERVICE"
part_number: "359"
part_name: "OFFERING OF UNITED STATES SAVINGS BONDS, SERIES I"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "5 U.S.C. 301; 12 U.S.C. 391; 31 U.S.C. 3105."
regulatory_source: "67 FR 64278, Oct. 17, 2002, unless otherwise noted."
cfr_part: "359"
---


# 359.16 When does interest accrue on Series I savings bonds?

(a) Interest, if any, accrues on the first day of each month; that is, we add the interest earned on a bond during any given month to its value at the beginning of the following month.

(b) The accrued interest compounds semiannually.