Another October Peak for Treasury Yields?

The 2026 rise in 10-year Treasury yields resembles 2023, but the forces behind it differ enough that October may not mark another peak.

• Through September 30, 2026, the 10-year yield had risen 112 basis points, almost matching the 110-bp increase recorded before the October 19, 2023 peak.
• September delivered the seventh consecutive month of higher 10-year yields, tying the longest such streak in 50 years; since 1980, however, January and March—not October—have been the most frequent peak months.
• In 2023, privately held net marketable borrowing reached roughly $1 trillion in the third quarter after the debt-ceiling impasse, while Federal Reserve balance-sheet reduction and a higher term premium also pushed yields higher.
• In 2026, Treasury borrowing is projected at $739 billion in the third quarter and $628 billion in the fourth, but the Fed’s balance sheet is roughly stable and energy-driven inflation, real yields and tighter policy expectations have played larger roles.
• The 2023 sell-off eased when the cash rebuild ended, long-dated issuance expectations were reduced, inflation softened and expectations for Fed policy became less restrictive.

Takeaway: October is not a reliable seasonal signal for a Treasury-yield peak; investors should focus instead on whether issuance pressures, inflation and monetary-policy expectations are losing force, while recognizing that the 2026 drivers are not identical to those of 2023.