Why Long-Term Borrowing Costs Are Back Over 5%
On September 28, 2026, the U.S. government paid 5.56% to borrow for 30 years and 5.24% to borrow for 10 years. Both numbers come from the Federal Reserve Bank of St. Louis FRED database for the DGS30 and DGS10 series. FRED FRED
Those series track a standard borrowing rate, called a yield, for 10- and 30-year government debt. The September 28 readings followed climbs through August and September. On August 17, 2026, the 30-year rose to 5.311%, its highest in 19 years. CNBC On September 15, 2026, the 10-year reached 5.041%, its highest since July 2007. CNBC On September 24, 2026, the 30-year hit 5.501%, a level not seen since June 2004. CNBC
The 10-year added roughly 20 basis points between September 15 and September 28. A basis point is a tiny step. One hundred steps make one full percentage point. The 30-year added roughly 19 basis points between August 17 and September 24, then rose further into September 28. The gap between the two September 28 rates, called the 10s30s spread, was 32 basis points. The long end sloped upward, and price sensitivity stretches out further along it.
Long comparisons for the 30-year have a break in the data. The 30-year series was stopped on February 18, 2002 and started again on February 9, 2006. FRED Any lookback across that gap bridges a time with no published 30-year reading.
The broader context here is what rates above 5% do to present value, the math that puts a price today on far-off payments. Think of a higher rate as heavier gravity on distant dollars. For pension-type accounts, that lowers the present value of future payouts and lifts funding ratios on paper. For bond portfolios judged on total return, the same rise brings price losses tied to modified duration and convexity, measures of rate sensitivity. Losses center further out.
Looking at what this means for positioning, the key items are term premium, or extra pay for lending longer, supply absorption, and discount rates across assets. A 32-basis-point spread pays for holding longer debt but gives little buffer if swings hit the long bond. Pension funds and insurers have long payouts that match up with it. Banks, mortgage portfolios, and leveraged holders of long duration do not.
In my view, the August-to-September tape reads as a supply-sensitive bear steepening, when long rates rise faster than short ones, rather than a simple parallel shift. The 10-year reclaimed ground last seen in July 2007. The 30-year then moved through its August high to levels tied to June 2004. Each leg held. That persistence tightens financial conditions through the discount channel even with no extra policy move stated in these data.
Risk management follows from that persistence. Higher yields reset coupons, or interest payments on new bonds, higher while pushing down clean prices on older low-coupon bonds. Roll-down changes. Hedge ratios set at lower yields drift. Anyone running DV01-based hedges, which track value change per basis point, needs to recalibrate to the new yield base, not the old one.
