Published October 16, 2026. Rate forecasts are labeled as forecasts; not financial advice.
Twice a year, on May 1 and November 1, the Treasury resets the rate on Series I savings bonds — the inflation-indexed savings bonds sold only through TreasuryDirect. The November 1, 2026 reset is shaping up as the most interesting one in years: September’s inflation report has already locked in a higher inflation rate, forecasters expect the bond’s permanent fixed rate to jump as well, and a combined starting rate around 5.4% is on the table.
There is a second deadline hiding inside the first one. On October 28, TreasuryDirect switches to ID.me as its only login method — three days before the new rate goes on sale. If you plan to buy in November, the login change matters as much as the rate. Here is what is known, what is still a forecast, and how to time a purchase.
Every I bond pays two rates stacked together:
The Treasury blends the two with its composite formula — fixed rate, plus twice the semiannual inflation rate, plus a small cross-term. Today’s bond shows how it works: a 0.90% fixed rate plus a 3.34% annualized inflation rate produces the current 4.26% composite rate for bonds issued May through October 2026 (TreasuryDirect, May 1, 2026). Interest accrues monthly and compounds semiannually.
Half of the November rate is not a forecast at all. The variable rate comes from CPI-U inflation between April and September 2026, and that data is final: non-seasonally adjusted CPI rose 2.04% over those six months, with the index reaching 336.940 in September, up 0.59% in the month alone (BLS data, via TIPSWatch, October 14, 2026). Doubled, that sets the new variable rate at 4.08%, up from 3.34% today. Every I bond — including one bought in 2021 with a 0.0% fixed rate — will earn that 4.08% annualized rate for six months once its next reset arrives.
The fixed rate is the unknown. David Enna of TIPSWatch, who estimates the fixed rate from average five-year TIPS real yields, expects the Treasury to raise it from 0.90% to at least 1.30% on November 1, with 1.40% possible if the Treasury follows its past practice (TIPSWatch; USA TODAY, October 16, 2026). Run those through the composite formula:
| Scenario (Nov 1, 2026) | Fixed rate | Variable rate | Starting composite |
|---|---|---|---|
| Buy through Oct 31 | 0.90% | 3.34% | 4.26% |
| Nov, fixed at 1.30% | 1.30% | 4.08% | ~5.41% |
| Nov, fixed at 1.40% | 1.40% | 4.08% | ~5.51% |
Table: current row per TreasuryDirect (May 1, 2026). November rows are estimates — variable rate from final CPI data, fixed rate per TIPSWatch forecast; composite computed with the Treasury formula. Official rates publish November 1, 2026.
Two cautions belong right next to that table. First, the composite rate is a starting rate: it holds for six months, then your bond moves to whatever variable rate comes next. Second, the Treasury sets the fixed rate by its own judgment and is not required to follow the TIPS-based formula — 1.30% is a well-grounded forecast, not a promise.
It is tempting to focus on the headline — 4.26% now versus roughly 5.4% in November. But the variable rate is shared: an October buyer’s bond picks up the 4.08% variable rate at its own six-month reset, paying roughly 5.00% for the second six months. The durable difference is the fixed rate. Buy in October and 0.90% is stitched into your bond for as long as you hold it, up to 30 years. Buy in November and you likely keep 1.30%–1.40% for that same span.
That 0.4 to 0.5 percentage point gap sounds small. On a $10,000 bond it is roughly $40–$50 of extra interest every year, before compounding, for as long as you hold the bond — and it is paid in good inflation years and bad ones alike. The first six months’ headline gap closes on its own; the fixed-rate gap never does.
On ratee’s tables verified October 12, 2026, the top high-yield savings APY is 5.00% (Axos ONE, with checking and direct-deposit conditions) and the top no-requirements rate is Elevault’s 4.34%. The top tracked CD pays 5.25% — but that is a 60-month lock on the CD rates page. A 26-week Treasury bill yielded 4.314% at its October 5 auction, as covered in our T-bills vs. high-yield savings guide.
Against that field, a ~5.4% starting composite is strong — with two honest asterisks. The rate floats with inflation after six months, so it is not a five-year lock like the CD. And the $10,000 annual cap means I bonds are a sleeve of a cash plan, not the whole plan. Model the mix with the savings calculator.
TreasuryDirect is replacing its traditional login with ID.me. Setup has been available since September 13, 2026; the old login works until October 28, 2026, after which ID.me is the only way in (TreasuryDirect FAQ, via USA TODAY, October 16, 2026). Skip the switch and you simply cannot log in online — your bonds and funds stay intact and are not frozen or seized, but you cannot buy the new-rate bonds on November 1, redeem anything, or download January tax forms until you enroll.
Practical advice: set up ID.me this week, starting from TreasuryDirect.gov directly rather than an emailed link, and expect the verification steps (government photo ID and identity checks) to take longer than a normal password reset. Doing it before the late-October rush beats debugging it on November 1.
You have not used your 2026 limit, the money can sit untouched for at least a year (ideally five), and you want the highest fixed rate locked for the long term. November’s expected 1.30%–1.40% fixed rate is the prize.
You might need the money within 12 months, or you have already bought $10,000 in 2026. Keep that cash in a top savings account and take the new fixed rate with your January 2027 limit instead.
This article is for informational purposes only and is not financial advice. The November fixed rate is a forecast until the Treasury announces it on November 1, 2026.
The Treasury announces the new fixed rate and composite rate on November 1, 2026. One half is already determined: the inflation (variable) rate will be 4.08%, because it is calculated from April-September 2026 CPI data, which is final. Only the fixed rate remains unknown until the announcement.
No. The 4.08% variable rate is set by published CPI data, but the fixed rate is the Treasury's choice. TIPSWatch forecasts 1.30%, possibly 1.40%, based on the Treasury's past practice of tracking five-year TIPS real yields. The Treasury is not bound by that formula and could set a different fixed rate on November 1.
You lock the current 0.90% fixed rate for the life of the bond and earn the current 4.26% composite rate for your first six months. After that, your bond picks up the new 4.08% variable rate too — old and new bonds share the variable rate — so your second six months would pay roughly 5.00%. What you give up is the higher fixed rate, which new buyers keep for up to 30 years.
After October 28, 2026, ID.me is the only way to log in to TreasuryDirect online. Your account and bonds remain intact — TreasuryDirect says funds will not be frozen or seized — but you cannot access the account online, buy new bonds, or download tax forms until you complete ID.me sign-up.
The standard limit is $10,000 in electronic I bonds per person per calendar year. The old extra $5,000 in paper bonds via a tax refund ended January 1, 2025. Gift bonds held in your TreasuryDirect gift box count toward the recipient's limit in the year you deliver them, and a fresh $10,000 limit opens on January 1, 2027.
This article is the starting point. Copy any of these prompts into your favorite AI assistant to learn more about Series I savings bonds and the November 2026 rate reset:
🔎 Price the wait: October’s 0.90% fixed rate vs. November’s forecast
Using the Treasury composite formula [fixed + 2 x semiannual inflation rate + (fixed x semiannual inflation rate)], compare a $10,000 I bond bought in October 2026 (0.90% fixed, 4.26% composite for six months, then a 4.08% variable rate) with one bought in November 2026 at a 1.30% fixed rate and the same 4.08% variable rate. Assume the variable rate then stays at 3.00% for the following four years. Show year-by-year values for five years, including the three-month interest penalty if I redeem at year five vs. just before it. Flag every assumption.
🧭 Fit I bonds into a full cash plan
I have $[AMOUNT] in cash: $[X] is an emergency fund I might need any month, $[Y] is for a goal in [NUMBER] years, and the rest is long-term savings. My state income tax rate is [X]%. Build a placement plan across a high-yield savings account, I bonds (respecting the $10,000 per person annual limit and 12-month lock), and Treasury bills. Explain the after-state-tax yield and access date for each slice.
💡 Verify the official rate when it drops on November 1
The Treasury announces new Series I bond rates on November 1, 2026. Tell me exactly what to check on TreasuryDirect's official rate release: the new fixed rate, the semiannual inflation rate, and the composite rate. Then recompute the composite from the fixed and variable components using the Treasury formula and tell me whether the announced composite matches, showing each step. If the fixed rate came in below 1.30%, explain what that changes about buying now vs. waiting for January's fresh purchase limit.
Tip: replace the bracketed parts with your own situation — the more specific your prompt, the more useful the answer.
The November 1, 2026 I bond reset pairs a variable rate that is already fixed by final CPI data (4.08%, up from 3.34%) with a fixed rate forecast to rise from 0.90% to 1.30%–1.40% — a starting composite around 5.4%, versus 4.26% for October buyers. The $10,000 annual cap, 12-month lock, and three-month early-redemption penalty still apply, and TreasuryDirect moves to ID.me-only login on October 28, three days before the new rate goes on sale.
The single most important point: wait for November if you can — not for the headline rate, which resets for everyone, but for the fixed rate, which is locked into your bond for up to 30 years. A 0.4–0.5 point fixed-rate edge pays you every year you hold the bond; the first six months’ headline gap pays you once.
One sharper AI prompt + one new interest-rate topic every week. Free forever, unsubscribe anytime.
We never share your email. One email a week, that's the deal.