History and Function of the Fed's Overnight Reverse-Repo Facility

MILES: How did the Feds overnight reverse-repo facility arise historically and what is it for now?

Pre-2008 regime: The Fed hit the federal funds target via reserve scarcity—small changes in reserve supply moved rates.

Shock: Global Financial Crisis → QE: Large-scale asset purchases made reserves abundant, so scarcity control stopped working.

First fix: Interest on reserves (IOER/IORB) to set a floor.

Leak in the floor: Key cash lenders—money market funds and GSEs (e.g., Fannie Mae, Freddie Mac)—cannot earn IOER, so their funds lent below the intended floor, pulling overnight rates down.

Solution (2013–2015): ON RRP—a standing facility that extends a Fed-set overnight rate to nonbanks, closing the segmentation gap.

Mechanics: The Fed borrows cash overnight via reverse repos, posting Treasury collateral and paying the ON RRP rate to eligible counterparties (MMFs, GSEs, some dealers/banks). It scales elastically (hundreds of billions to trillions).

Current functions: (1) Hard floor for rates: ON RRP is the outside option for nonbanks; together with IOER it forms a floor system (banks via IOER, nonbanks via ON RRP), anchoring fed funds, repo, and T-bill rates. (2) Liquidity sink/pressure valve: Absorbs excess cash (from QE, Treasury cash swings, etc.), preventing rate collapses in abundant-liquidity states. (3) Stabilizer of money markets: Provides an elastic safe asset, dampening volatility and backstopping repo when private balance sheets are constrained.

Conceptual interpretation: ON RRP extends the Fed’s interest-bearing liabilities beyond banks to the whole money market—effectively a close T-bill substitute issued by the Fed—which is what makes the ample-reserves operating regime work.

Implications: It blurs reserves vs. short Treasuries, competes at the margin with private repo intermediation, and is central to reliable short-rate control under abundance.