Corporate cash policy is now a plumbing decision, not a yield one

Record money fund balances, thinner market underneath

Bloomberg reported on May 29, 2026 that US money market fund assets reached a record $8.281 trillion, with uncertainty over the Fed's policy path driving demand for cash-like instruments. That is a long way from the Investment Company Institute weekly series first crossing $7 trillion in late 2024 and printing $7.03 trillion for the week ended March 5, 2025.

The problem is what sits beneath those balances. Bank reserves fell to roughly $2.8 trillion by late October 2025, the lowest level in more than four years, and on October 31, 2025 the Fed executed a $29.4 billion overnight operation through its Standing Repo Facility. Government money funds are, in substance, large repo lenders. When repo gets tight, the fund your operating cash sits in is not a passive observer.

What the Fed changed in December 2025

Two official actions reset the backstop. The New York Fed's Teller Window noted on December 23, 2025 that the FOMC had eliminated the $500 billion aggregate daily limit on standing repo operations at its December meeting. Separately, the Fed restarted reserve management purchases of $40 billion per month from December 10, 2025.

Capacity is not the same as usage. Capital Advisors Group wrote in December 2025 that repo rate volatility had increased around month-end reporting periods and was only slightly mitigated by the Standing Repo Facility, which had fallen short in practice because of underutilization. Usage has since risen sharply, with ProSight Financial Association reporting a steep increase in bank and dealer participation and Barron's putting October borrowing at roughly $110 billion. Stigma still bites, and stigma is precisely what fails at the moment you need the facility to work.

Quarter-end is where the calendars collide

Repo dislocations cluster at month and quarter ends because dealer balance sheets are being measured. Those are the same dates on which corporate treasuries fund payroll, estimated tax payments and debt service. A SOFR spike does not simply mean a better overnight rate next week. It means government fund yields, repo collateral availability and same-day redemption behaviour all move together, on the day your operating account needs to be funded.

That is the case for treating the September quarter-end repo print as a policy event rather than a market-commentary item. If the facility absorbs the pressure cleanly, the current policy is probably fit for purpose. If spreads gap and SRF usage jumps again, the treasurer's assumption that a government fund is a same-day cash equivalent deserves a written stress test, not a footnote.

Five changes to take to the board

First, stress the quarter-end redemption window specifically: model a same-day redemption request on September 30 rather than an average business day, and document what the fund's disclosed liquidity would support. Second, cap single-fund concentration in hard dollars, not percentages that drift as the balance grows. Third, document the prime versus government allocation and the reason for it, using the Office of Financial Research's Money Market Fund Monitor to track how the split is moving across the industry.

Fourth, confirm intraday liquidity lines with your banks in writing, including what happens if a redemption settles late. Fifth, put the question to the board directly: does an investment policy drafted for a yield decision still describe a market the Fed is actively backstopping? The honest answer for most companies is no, and the fix is a paragraph on liquidity mechanics rather than a wholesale change in instruments.

Verify the numbers before you cite them

Every figure here carries a date. Money fund assets move weekly, SRF usage moves daily, and reserve levels move with the Fed's balance sheet operations. Re-pull the current ICI weekly release and the latest quarter-end repo prints before any of this goes into a board paper. The argument is durable; the data points are not.