September 2024 CPI-U numbers released: Neutral on I Bonds Purchase

The U.S. Bureau of Labor Statistics released the September 2024 Consumer Price Index (CPI-U) inflation data last week, which increased by 0.160% over the past month.

As always, now is one of the best times to consider purchasing I Bonds. The reason for this is that we now know what the rate of return for October 2024 I Bonds will be for both the first and second six month periods, which is important since I Bonds must be held for 12 months before they can be redeemed.

Using the CPI-U data from March 2024 (312.332) and September 2024 (315.301) (courtesy of inflationdata.com), we can calculate the variable rate for the second 6 month period for October 2024 issue I Bonds.

That means these bonds would earn the current rate of 4.28% (using 1.3% fixed & 1.48% variable) for the first 6 months and 3.21% (combined 1.3% fixed & 0.95% variable) for the second 6 months. In the current interest rate environment, an October I Bond purchase is a reasonable choice when compared to something like the 52 Week T-Bills @ 3.946% APY issued on 10/3/2024.

In my opinion, October 2024 I Bonds are a reasonable choice, particularly for the 1.3% fixed rate if you plan to hold them long term. Based on the spread between I Bonds and TIPS, David Enna of tipswatch.com projects that the new fixed rate will fall slightly to 1.20%, which would make a purchase before the end of the month even more attractive. I've already maxed out my 2024 I Bond limit, so I'll evaluate them again in April 2025 once the March 2025 CPI-U numbers are released.