Fannie Mae, Freddie Mac Add $135 Billion in Portfolios as Duration Gaps Widen to 1 Year
Updated
Updated · The Wealth Advisor · Jun 25
Fannie Mae, Freddie Mac Add $135 Billion in Portfolios as Duration Gaps Widen to 1 Year
3 articles · Updated · The Wealth Advisor · Jun 25
Summary
More than $135 billion of retained portfolio growth over the past year has left Fannie Mae and Freddie Mac carrying duration gaps of roughly one year, sharply increasing their sensitivity to rate moves.
A 50-basis-point rise in rates could cut Fannie Mae’s portfolio value by about $1.2 billion and Freddie Mac’s by more than $1.6 billion, as the agencies hold more mortgage-backed securities and tolerate more unhedged extension risk.
That shift supports housing affordability by boosting demand for agency MBS and helping restrain mortgage yields, but heavier hedging through Treasuries and derivatives could itself push benchmark yields higher.
Freddie Mac says the new structure steadies income—its expected coupon-income hit from a 100-basis-point rate drop falls to about $343 million from $492 million—but exposes it to roughly $3.4 billion of mark-to-market losses in an adverse 100-basis-point shift.
Combined agency holdings remain a small slice of the $8.5 trillion agency MBS market and capital buffers are stronger than before 2008, leaving investors broadly viewing the rising risk as manageable for now.
As mortgage giants gamble on interest rates, what does this signal for the broader bond market?
Is the government's housing push creating a hidden time bomb in the mortgage market?
Fannie and Freddie’s Portfolio Surge: How a $200 Billion MBS Buying Spree Is Reshaping Housing Risk and Affordability
Overview
This report highlights how the growing portfolios of Fannie Mae and Freddie Mac are central to financial stability, especially as their widening duration gaps make them more vulnerable to interest rate changes. Such increased sensitivity can affect both their financial performance and the broader housing market. While single-family mortgage delinquency rates remain generally low, the inclusion of loans in forbearance in delinquency counts—despite not being reported as delinquent to credit bureaus—provides a fuller picture of potential risks ahead. Together, these factors underscore the importance of monitoring both portfolio growth and risk metrics to safeguard market stability.