Mortgage Bond Purchases Peak in April as Treasury Debt Climbs $17 Trillion

Government-sponsored enterprises bought mortgage securities at their fastest pace in the spring, even as the federal debt load has grown sharply since the pandemic.

By the Family Office Real Estate Daily Desk·Thursday, October 15, 2026·2 min read

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Have Fannie Mae and Freddie Mac actually been buying mortgage bonds as directed, and what does slowing GSE buying mean for mortgage rates?

Fannie Mae and Freddie Mac mortgage-bond purchases peaked in April 2026 and have since declined, even as total federal debt reached $40.31 trillion—up $16.9 trillion since February 2020. Combined GSE net buying reached roughly $39 billion over eight months, about one-fifth of the $200 billion White House directive, leaving the mortgage market with fewer bond buyers and a spread that widened to 2.12 percentage points.

Key facts

Fannie Mae's agency mortgage securities rose from $71.5 billion at year-end to $110.5 billion in April, then slid to $99.8 billion by August, according to Fannie Mae's own monthly filings.
Freddie Mac's mortgage security holdings went from $44.6 billion to $55.6 billion by February and have sat near $55 billion since, according to Freddie Mac's monthly filings.
Combined GSE net buying totaled roughly $39 billion over eight months—about one-fifth of the $200 billion directive issued in January—and sat $11.6 billion below the April peak, according to The Skeptical Investor Newsletter's calculations from Fannie Mae and Freddie Mac filings.
Total federal debt was $23.41 trillion on February 28, 2020, and $40.31 trillion on October 8, 2026, up $16.9 trillion or 72%, according to the U.S. Treasury.
In fiscal 2026, net interest on the federal debt was $1,143 billion, surpassing the Defense Department's $916 billion in spending by roughly $227 billion, according to the Congressional Budget Office.
A lender group has written to FHFA Director Bill Pulte and Treasury Secretary Scott Bessent estimating that full GSE participation in mortgage-bond buying could cut spreads 10 to 12 basis points, according to Scotsman Guide.

Mortgage Bond Purchases Peak in April as Treasury Debt Climbs $17 Trillion — Image: editorial illustration · Story sourced from andreasmueller.substack.com

Fannie Mae and Freddie Mac bought mortgage-backed securities at peak volume in April, according to their monthly filings, even as the White House in January directed the government-sponsored enterprises to purchase $200 billion of the bonds. The purchases have since moderated, the filings show.

The U.S. has added almost $17 trillion of debt since Covid, according to data cited in a newsletter by Andreas Mueller. The 10-year Treasury yield and the spread between mortgage bonds and Treasuries together determine mortgage rates, which have historically carried a spread of about 1.6 to 1.8 percentage points over the 10-year, HousingWire reported.

The 30-year mortgage rate stood at 7.48% as of mid-October, down 0.09 percentage points from the prior week, Mortgage News Daily said. Energy prices rose 16.3% in August from a year earlier, the Bureau of Labor Statistics said, while core CPI, which excludes food and energy, ran at 2.4%. Overall CPI was 3.4%.

The economy added 29,000 jobs in September, the Bureau of Labor Statistics said. Unemployment ticked up to 4.2%, and July and August payrolls were revised down a combined 60,000. The University of Michigan's sentiment index fell to 46.3 in early October, down 13.6% from a year earlier, with one-year inflation expectations at 4.7%, Advisor Perspectives said.

Home sales fell 5.6% from August, and newly pending sales dropped 11.2%, Zillow said in its September report. The typical rent rose 2.7% from a year ago to $1,932, the fastest rent growth since April 2025, Scotsman Guide said. The typical mortgage payment now takes 34.3% of median income, versus 26.3% for rent, Zillow said.

Zillow's chief economist said marginal buyers find the savings from renting too good to pass up. The Department of Housing and Urban Development on October 7 released a seven-step plan to modernize the manufactured-housing code, including a performance-based federal code for factory-built buildings with five or more units, HUD said. In 2023, a new manufactured home cost about $87 a square foot versus about $166 for a site-built house, excluding land, Census data showed.

The Federal Reserve raised its target range to 3.75% to 4.00% in September, according to FOMC minutes. Prediction markets put the odds of a hold at the October 27-28 meeting near 83%, but the odds of a hike at the December 8-9 meeting near 75%, an average of DefiRate, Kalshi and Polymarket showed.

The Deployment Angle

Family Office Real Estate Daily Desk · our analysis, not the source's

The divergence between White House directives and actual GSE purchase activity argues for stress-testing rental acquisition models against a wider mortgage spread. If the historical 1.6 to 1.8 percentage-point spread over Treasuries widens by even 25 basis points, a $10 million multifamily acquisition financed at 65% loan-to-value sees its annual debt service rise by roughly $16,000, compressing cash-on-cash return by about 45 basis points on a $3.5 million equity cheque.

The arithmetic on manufactured housing is stark. At $87 per square foot versus $166 for site-built, a 50-unit apartment project pencils at roughly half the construction cost if HUD's proposed code takes effect. A family office writing a $15 million cheque for new supply should model two scenarios: one in which the code is approved within 18 months and factory-built competition compresses rents in tertiary markets, and one in which rule-writing drags past 2028 and the cost advantage never materializes. Price the option value of waiting accordingly.

The shift from ownership to rental demand is a call option on multifamily platforms in markets where mortgage payments take 30% or more of median income. Nashville, where unemployment remains among the lowest of any large metro, fits that profile. A programmatic joint venture with a sponsor focused on workforce housing in job-growth metros captures the marginal buyer who stays a renter, but only if the platform can source deals at replacement cost or below. Co-GP structures that rely on merchant-build economics face headwinds if factory-built supply scales faster than expected.

Direct ownership of stabilized rental product in markets with sub-4% unemployment and positive net migration remains defensible, but underwrite to a scenario in which the Fed hikes in December and mortgage rates hold above 7% through the first half of 2027. That compresses exit multiples and argues for longer hold periods. Avoid leverage above 55% loan-to-value on floating-rate debt unless the sponsor has locked interest-rate caps through at least mid-2028.

Questions this story answers

01Are Fannie Mae and Freddie Mac actually buying mortgage bonds in large quantities right now?

FHFA Director Bill Pulte said on September 18 that Fannie Mae and Freddie Mac were 'beginning to buy even more, large quantities, as we speak,' according to Scotsman Guide. However, Fannie Mae's and Freddie Mac's own monthly filings show combined holdings peaked in April and have declined since, with net buying of roughly $39 billion over eight months—about one-fifth of the $200 billion White House directive.

02How much has US federal debt grown since the pandemic and why does it matter for real estate?

Total federal debt rose from $23.41 trillion on February 28, 2020, to $40.31 trillion on October 8, 2026—an increase of $16.9 trillion or 72%, according to the U.S. Treasury. Greater Treasury supply may force investors to demand higher yields on the 10-year, pushing up mortgage rates, while a retreating government mortgage buyer leaves fewer hands for mortgage bonds and widens the spread.

03How wide is the mortgage spread right now and what does it mean for borrowing costs?

The mortgage spread widened to 2.12 percentage points from 1.98 the week before, according to HousingWire. The historical spread has run about 1.6 to 1.8 percentage points. On a $400,000 loan at 7.48%, every 20 basis points of spread adds about $55 a month, or roughly $19,800 over 30 years, according to The Skeptical Investor Newsletter's calculations.

04What is the current 30-year mortgage rate and where is the broader economy heading?

The 30-year mortgage rate stood at 7.48% as of the article's publication, down 0.09% from the prior week, according to Mortgage News Daily. The economy added just 29,000 jobs in September, unemployment ticked up to 4.2%, and July and August payrolls were revised down a combined 60,000, according to the Bureau of Labor Statistics.

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