US Treasury 30-Year Auction Tails by 0.4 Basis Points, Pushing 10-Year Yields Above 5.10%

The U.S. Treasury sold $25 billion of 30-year bonds, with the auction stopping at a high yield of 5.441%, according to auction results. That was lower than last month's 5.618% high yield, but the sale still tailed the expected yield by 0.4 basis points, the largest tail since June and the second-highest since November. The weak tail helped push 10-year Treasury yields above 5.10% during the session.

The auction's bid-to-cover ratio, a measure of demand relative to supply, fell to 2.401 from 2.542, the lowest since August and below the six-auction average of 2.437. Indirect bidders, often foreign or institutional buyers, took 68.1%, down from 72.3% and below the recent average of 70.5%. Direct bidders held roughly steady at 20.5%, while dealers absorbed 11.4%, the highest share since June.

The result followed a weaker 10-year auction earlier in the week and occurred amid a broader decline in yields after turmoil in artificial-intelligence stocks, which reduced competition for long-dated paper. A tail means the auction's clearing yield was higher than the prevailing when-issued yield, signaling bidders required extra compensation. The 30-year sale was less severe than the 10-year auction, but still pressured the long end.

The auction matters because long-term Treasury yields set a benchmark for government borrowing and influence broader credit costs, including mortgages and corporate financing. The shift in bidder mix, with dealers taking more paper and indirects receding, shows weaker appetite for long-duration U.S. debt at the offered yields. That combination raises the cost of financing fiscal deficits and places pressure on financial conditions for borrowers worldwide.