Morgan Stanley: Fed Balance Sheet Runoff Does Not Equal Tightening — $1.5 Trillion Can Be Unwound with Low Market Impact
Miles Bennett
Morgan Stanley chief economist Seth Carpenter argues the Fed can shrink its balance sheet by roughly $1.5 trillion over the coming years with far less market disruption than expected — because runoff and tightening are not the same thing, and markets have confused the two for years.
Why doesn't shrinking the balance sheet equal tightening?
Carpenter's core argument: balance-sheet size and monetary-policy stance are two independent dimensions — one cannot proxy for the other.
This means → the old framework of "Fed runoff = automatically bearish for risk assets" may be fundamentally wrong.
His own words are blunt: the coming policy debate is "more about accounting than about markets."
How do you shrink $1.5 trillion? What tools are available?
The Treasury General Account is the most direct lever. The Treasury currently holds roughly $800 billion to $1 trillion in cash at the Fed; cutting up to $500 billion would directly compress the balance sheet with zero market impact.
Foreign official reverse-repo balances — short-term funds parked at the Fed by foreign central banks — have swollen to about $350 billion. The Fed can adjust terms to bring them down.
The most consequential tool is tiered reserve remuneration: slashing the interest paid on banks' excess reserves (cash banks keep at the Fed beyond what they need) well below short-term Treasury yields, pushing banks to swap reserves for T-bills. In plain terms = money isn't drained from the system; it just moves — off the Fed's books and into the Treasury market.
Once banks move their money out, can the Treasury market absorb it?
Carpenter estimates that issuing roughly an extra $1 trillion in short-term T-bills would keep the share within its historical normal range.
This means → the Treasury simply issues more bills to meet the new demand from banks, and supply lines up with demand — no extra duration pressure is created.
In plain terms = the market's biggest fear — "runoff pushes long-term rates higher" — may not materialize under this playbook, because the released supply is concentrated at the short end and long-end duration risk does not rise significantly.
Where are the risks?
The biggest risk is active MBS sales — mortgage-backed securities, assets created when banks packaged home loans and sold them to the Fed. A large-scale sell-off would carry non-trivial market impact.
Another variable is the Treasury's own issuance decisions. The Fed's balance sheet is not the only moving part; whether the Treasury chooses to fund long or short directly determines how much duration the market must absorb.
This reflects a deeper point: whether runoff can be done with "low impact" does not depend on the Fed alone — it requires Treasury cooperation.
Who is pushing this, and will markets buy it?
The report notes that current Fed Chair Kevin Warsh has long favored reducing the Fed's market footprint. Morgan Stanley judges that substantive runoff is more likely than not.
Carpenter acknowledges that whether markets accept this view will be the core disagreement in the runoff debate ahead.
This means → even if the mechanics work on paper, whether markets can let go of the instinctive "runoff = tightening" reaction is the real test.
Content is for reference only, not financial advice.