Integrated Brief

Treasury Bills Share of Marketable Debt

As of 2026-09-30, the Treasury Bills Share of Marketable Debt stood at 22.36%, down 0.41 pp from the prior reading, at the 90th percentile of the past 5 years. MSPD Table 1 — Treasury bills (securities maturing in one year or less) as a share of total marketable Treasury debt outstanding, from the Treasury's Monthly Statement of the Public Debt. Treasury's own debt-management advisory committee (TBAC) has recommended keeping this share in a roughly 15–20% band; a higher share means more of the debt stock has to be rolled over in the near term, which raises how sensitive federal borrowing costs are to short-term rate moves and how much bill supply money-market funds have to absorb. Monthly and slow: the point is stamped at month-end and released around the 8th business day of the following month, so the latest stamp can be close to six weeks old before the next one lands. A forward-looking structural indicator, not a coincident one — it speaks to issuance plans, not to current funding stress.