In the US commercial mortgage-backed securities (CMBS) market, single-loan structures clearly dominate activity. So-called single-asset, single-borrower transactions (SASB) accounted for 76 per cent of total private CMBS issuance volume by the end of September. Total volume during this period reached 87.2 billion dollars, representing a modest increase of two per cent compared to the equivalent months of 2025. SASB and large-loan structures reached 66 billion dollars, while traditional conduit structures generated just 21.2 billion dollars.
For every dollar invested in conduit bonds, 3.12 dollars were accounted for by single-loan structures. The balance of power has shifted noticeably in historical terms. In the first nine months of 2017, 2019, 2020 and 2023, conduit transactions still led the market; in 2017, the share of SASB deals stood at just 42 per cent. While conduit volume remained steady over the years within a range between 13 billion and 28 billion dollars, issuance volume for SASB formats more than doubled.
Reallocation of asset classes and monumental single assets
The list of largest transactions reflects some of the most prominent commercial properties in the United States. In February alone, the refinancing of The Cosmopolitan of Las Vegas hotel reached a volume of 3.05 billion dollars as a standalone bond. By contrast, this year's largest conduit issuance, BMARK 2026-V21, pooled a total of 49 loans to achieve an overall volume of 1.2 billion dollars. Fifteen SASB and large-loan deals comfortably surpassed this figure.
- —A residential portfolio in Jersey City, New Jersey, with a volume of 2.1 billion dollars
- —A portfolio of QTS data centres valued at 2.05 billion dollars, arranged by nine banks
- —The financing of the Two Manhattan West office complex in the amount of 1.9 billion dollars
- —Manhattan office and mixed-use towers such as 9 West 57th Street, One Madison Avenue and 10 Hudson Yards
Behind the figures, a noticeable shift in collateral is taking place. While conduits continue to serve the financing of standard commercial properties, with a residential share of 26 per cent and a retail share of 13 per cent across 1,067 loans with an average volume of 20 million dollars, major institutional capital is flowing into trophy assets. In SASB issuances, office volume fell to 12.5 billion dollars from 22.4 billion dollars in the previous year, and retail financing halved to 5.1 billion dollars. This was offset by residential property at 10 billion dollars, hotels at 11.3 billion dollars, and data centres, which reached a volume of 6.2 billion dollars.
Concentration among few banks and structural differences
Financing terms in the two segments also diverge significantly. Around 60 per cent of SASB volume was issued on a floating-rate basis. Conduit loans, by contrast, carry fixed interest rates without exception; 90 per cent of these loans are interest-only with a weighted average interest rate of 6.43 per cent.
The underwriting business is concentrated among a handful of players. Seven institutions account for 80 per cent of the recorded volume. Goldman Sachs leads the evaluation by CRED iQ with a total volume of 12 billion dollars, of which 10.1 billion dollars relates to SASB deals. Wells Fargo and Citi follow in the next positions, with Citi leading the conduit financing segment with 2.6 billion dollars. Morgan Stanley ranks fifth. While conduits serve the broader market tranche by loan tranche, institutional capital in 2026 is moving primarily through individual large-scale assets.
