High-quality corporate curve for August 2026 · U.S. Treasury HQM data, published monthly
In August 2026 a high-quality corporate bond maturing in ten years yielded 5.47%, +79 bp more than the 10-year Treasury, a spread that widened +4 bp from the month before. Over the past 5 years that spread has ranged from +68 bp in January 2026 to +175 bp in October 2022.
| Maturity | Corporate Par Yield | Corporate Spot Rate | Treasury | Spread | 1 Month | 1 Year Ago | 5 Years Ago |
|---|---|---|---|---|---|---|---|
| 1Y | — | 4.31% | 4.03% | +28 bp* | -2 bp | 4.21% | 0.26% |
| 2Y | 4.58% | 4.59% | 4.22% | +36 bp | +1 bp | 4.11% | 0.50% |
| 3Y | — | 4.75% | 4.28% | +47 bp* | +3 bp | 4.12% | 0.72% |
| 5Y | 4.94% | 4.97% | 4.38% | +56 bp | +8 bp | 4.32% | 1.17% |
| 7Y | — | 5.21% | 4.52% | +69 bp* | +11 bp | 4.65% | 1.70% |
| 10Y | 5.47% | 5.58% | 4.68% | +79 bp | +12 bp | 4.97% | 2.26% |
| 15Y | — | 5.98% | — | — | +13 bp | 5.57% | 2.87% |
| 20Y | — | 6.21% | 5.22% | +99 bp* | +14 bp | 5.81% | 3.00% |
| 30Y | 6.17% | 6.65% | 5.22% | +95 bp | +15 bp | 5.66% | 2.94% |
Corporate yields are the U.S. Treasury’s High Quality Market curve (AAA, AA and A rated bonds), monthly. Treasury yields are the Federal Reserve’s H.15 constant-maturity series for the same month. Spread is corporate par yield minus Treasury; where the Treasury publishes no par series for a maturity (*) the spot rate is used instead, and the 15-year has no Treasury counterpart. The 1-month, 1-year and 5-year columns follow the same par-then-spot rule.
Every corporate bond yield can be split in two. The first part is the Treasury yield of the same maturity, the rate the market charges for lending to the safest borrower there is. The second part is the credit spread: the extra return investors demand because a company, unlike the U.S. government, can fail to pay. A small third component covers liquidity, since even a large corporate issue trades in a fraction of the volume a Treasury does and is harder to sell in a hurry.
That decomposition is why there is no single number called the corporate bond yield. It depends on the maturity, which sets the Treasury component, and on the credit quality of the borrower, which sets the spread. A two-year bond from a AA-rated utility and a ten-year bond from a B-rated retailer can differ by five percentage points or more while both being called corporate bonds. The table above fixes the quality at the top of the investment-grade range and shows how the yield changes with maturity alone.
The High Quality Market curve is built each month by the U.S. Treasury from a large sample of corporate bonds rated AAA, AA or A. It exists for a practical reason: pension plans governed by the Pension Protection Act must discount their future obligations at high-quality corporate bond rates, and the Treasury supplies the official curve those discount rates are drawn from, projecting it out to a hundred years to cover the longest liabilities. The one-to-thirty-year section shown here is the part that describes the bonds companies actually issue.
The methodology estimates spot rates, the yield on a single payment at each maturity, and then derives par yields, the rate a coupon-paying bond priced at 100 would carry, for the benchmark maturities. Par yields are the figures to compare against a bond quote, which is why the tiles at the top of the page use them. The spot rates give the full curve at every maturity, including the fifteen-year, where no Treasury benchmark exists.
What the curve is not: it says nothing about BBB-rated debt, the largest slice of the investment-grade market, and nothing about high yield. Those yields sit above every number on this page, by a modest margin for BBB and by several points for the riskiest credits.
Rating agencies grade corporate borrowers on a ladder that runs from AAA at the top down through AA, A and BBB, then into BB, B and CCC. The line between BBB− and BB+ is the one that matters most, because it separates investment grade from high yield, and many institutional mandates can hold only the former. A company downgraded across that line, a fallen angel, sees its bonds sold by investors who are no longer allowed to own them, which is why the boundary is priced with a visible jump in yield rather than a smooth step.
BBB has become the centre of gravity of the market: roughly half of all investment-grade corporate debt now carries that rating, up from a quarter a generation ago, as companies have chosen to borrow more and accept a lower grade. High yield yields several percentage points more than the curve above and moves far more with the economic cycle. The daily high-yield and investment-grade index spreads are published by ICE Data Indices and are available free on the Federal Reserve Bank of St. Louis’s FRED site, for example the high-yield option-adjusted spread. They are licensed data that cannot be republished here, so we point to the source rather than reprint them.
Spreads are a forecast of defaults, discounted by the market’s appetite for risk. In a growing economy with easy financial conditions they compress, sometimes to levels that later look reckless; in a downturn they gap wider as investors demand more compensation at exactly the moment companies most need to refinance. The 10-year history chart above shows the pattern: the corporate line rides a fairly steady distance above the Treasury line for years and then the gap opens abruptly, as it did in late 2008 and again in March 2020, before closing over the following year.
Federal Reserve policy matters through two channels. Rate changes move the Treasury component directly, and the Fed’s willingness to support credit markets, as it did in 2020 by buying corporate bonds for the first time, changes the spread by changing the perceived floor under prices. Supply matters too: heavy issuance waves, often triggered by companies rushing to lock in rates before an expected rise, push spreads wider until the new bonds are absorbed. And sector shocks can move the average without moving most companies, as the 2015–16 collapse in energy prices did through the oil and gas issuers.
The most direct use is as a yardstick. A bond offered to you at a given maturity should yield around the curve’s figure for its rating tier; materially more usually means more risk than the rating suggests, materially less means you are paying for a name or for convenience. For a fund rather than a single bond, the curve tells you what the underlying holdings are earning before fees, which is the number a fund’s distribution yield will drift toward over time.
Two comparisons are worth making before buying corporate paper at all. Against Treasuries, the question is whether the spread pays for the default and liquidity risk you are taking; the five-year range in the summary above puts today’s spread in context. Against municipal bonds, the comparison must be made after tax, since municipal interest is generally exempt from federal income tax and corporate interest is not, which can erase a corporate yield advantage of a point or more for investors in high brackets.
Sources: U.S. Department of the Treasury, High Quality Market (HQM) Corporate Bond Yield Curve, monthly; Board of Governors of the Federal Reserve System, H.15 Selected Interest Rates. Both retrieved via FRED, Federal Reserve Bank of St. Louis. Public-domain U.S. government data. This page is information, not investment advice; see our disclaimer.