About the DUS® model
For over 35 years, Fannie Mae has been a trusted leader in the multifamily housing market, committed to supporting quality, affordable rental housing in America. Our innovative Delegated Underwriting and Servicing (DUS) model — built on delegation, risk-sharing, and life-of-loan servicing — enables us to serve every market, every day.
We acquire multifamily loans mainly from our national network of DUS Lenders. These loans are secured by multifamily properties. We securitize the loans into DUS Mortgage Backed Securities (MBS) which investors may keep for their own portfolios or sell to the market. We also buy and sell DUS MBS in the secondary market, allowing investors to create structured securities backed by these assets. Our platform supports borrowers, lenders, and investors alike — because The Loan We All Own® is more than a tagline; it’s our mission in action.
Nothing we do is possible without our DUS lender partners. They test new technology and ways of working that help us build faster, smarter systems. They’re committed to creating and preserving housing that produces positive outcomes for renters. And every day, they prove that we can achieve more together.
We set the standard
As one of the largest guarantors of mortgages in America, we play a major role in setting standards for the housing finance market. We drive market practices through our underwriting Guide, disclosure and asset management tools, data standards, and constant engagement with our lender partners. By integrating time-saving digital tools into the loan process, we simplify lending operations and empower lenders to deliver rental housing to the market more efficiently.
The DUS model participants
We set the standard
As one of the largest guarantors of mortgages in America, we play a major role in setting standards for the housing finance market. We drive market practices through our underwriting Guide, disclosure and asset management tools, data standards, and constant engagement with our lender partners. By integrating time-saving digital tools into the loan process, we simplify lending operations and empower lenders to deliver rental housing to the market more efficiently.
Multifamily by the numbers
$500+ Billion
Guaranty book of business
15.3+ Million
Units financed
95%+
Of the units we financed in 2024 are affordable to working families*
Data as of June 2025
*Defined as families earning at or below 120% of area median income.
DUS benefits
We finance all loan sizes, from a $1 million single-asset MBS to a $1+ billion structured transaction. We all share the risk, and we all share the reward.
Reliable
We deliver consistent liquidity and stability to the housing market – backed by strong credit standards in order to increase access to quality affordable housing.
Fast & certain
Our DUS model empowers our DUS lenders to underwrite and close loans on our behalf, enabling faster decisions, quicker closings, and certainty of execution through a unique risk-sharing partnership.
Life-of-loan servicing
No other master or special servicer and smooth post-closing activities. This life-of-loan relationship also increases efficiencies across second liens, supplementals, and refinances.
Optimized
With a full service, nationwide team and a flexible platform that supports all asset types and loan sizes, we're built to lead the market — leveraging private capital, and deep market expertise to get the right deals done.
DUS features
We consistently provide access to credit throughout economic cycles. When other sources of capital retreat, Fannie Mae is still there to provide funding and liquidity.
Our underwriting and servicing guidelines and loan documents set the industry standard for multifamily underwriting and servicing best practices, promoting standardization and transparency, and facilitating reliable securities disclosures.
Our unique delegated model can scale our business as market conditions change, because we delegate underwriting and servicing to our DUS Lenders.
We maintain strong relationships with our DUS Lenders, who all exhibit:
- Financial strength.
- Extensive multifamily underwriting and servicing experience.
- Strong portfolio performance.
- Creation of quality branded products.
The interests of borrowers, lenders, and Fannie Mae are aligned throughout the life of the loan. We believe this alignment of interests improves the performance of all parties and optimizes outcomes.
Our DUS MBS, backed by a single asset, transforms a mortgage loan into a more liquid asset, which increases available funds in the financial system. Our securities offer strong credit ratings as Fannie Mae guarantees timely payment of both principal and interest.
Supporting affordable housing
We're committed to preserving and financing quality affordable rental housing nationwide. Our financing solutions support the delivery of rental units for all income ranges – and are designed to support affordable housing goals. Here are some of the solutions we offer.
Affordable Housing Preservation
Partner with our Affordable team to find the right solution for your next deal.
$500+ billion total book of business
*data as of year end 2024
Structured Transactions
Our finance solutions include Credit Facilities and Bulk Deliveries to offer flexible, scalable options with variable- and fixed-rate debt, laddered maturities, and post-closing flexibility.
Our team supports financing across all property types, from market-rate to Affordable, Student Housing, and Manufactured Housing.
$63.6+ billion for Credit Facilities and Bulk Delivery
*data as of year end 2024
Sponsored-Dedicated Workforce
Sponsored-Dedicated Workforce supports the creation of affordable housing for workforce renters by offering competitive pricing and flexible underwriting. Borrowers who commit at least 20% of units to renters earning up to 80% AMI — or up to 100–120% AMI in high-cost markets — can benefit from this private-market solution.
$3.2+ billion financing for workforce housing properties meeting specified criteria that preserve long-term affordability for the properties
*data as of year end 2024
Low-Income Housing Tax Credit (LIHTC)
We invest in LIHTC equity to help create and preserve affordable housing for low- and very low-income renters. In LIHTC investments, we focus on communities that include rural communities, Native American lands, or areas impacted by natural disasters.
$4.7+ billionIn equity since re-entering the market in 2018.
Manufactured Housing Communities
We're leading the way in supporting renters in MHCs. Our financing includes Tenant Site Lease Protections and discounted options for nonprofits, government entities, and resident groups. We also focus on rural markets as part of our Duty to Serve plan.
$20+ billion book of business
*data as of year end 2024
Green Financing
Since launching in 2012, Fannie Mae’s Green Financing program has helped make rental housing more energy- and water-efficient. Borrowers can access Green Financing through two pathways including Green Rewards for existing properties seeking to make efficiency improvement, and Green Building Certification for their property.
$132+ billion in green bonds issued
*data as of year end 2024
Duty to Serve
Fannie Mae’s Duty to Serve efforts focus on expanding access to affordable housing in key markets: manufactured housing, rural housing, and affordable housing preservation.
Through Duty to Serve, we help increase financing options, support innovative housing solutions, and preserve affordability where it’s needed most.
973,000+ rental units