Trepp | Large New York Loans Are Driving 2026 Office CMBS Origination Volume, and Carrying Lower Debt Yields

New York single-asset, single-borrower (SASB) loans account for 60% of private-label office commercial mortgage-backed securities (CMBS) loan volume originated through August 4, 2026, while urban SASB loans carry substantially lower median debt yields than urban conduit loans.

Private-label CMBS loans backed by office properties and originated from January 1, 2026, through August 4, 2026, totaled $18.3 billion across 91 whole loans. Among loans that remain outstanding and non-defeased, that volume was 25% higher than the comparable total for loans originated during the same period of 2025. Because the older cohort excludes loans that have since been repaid or defeased, the 25% figure should be interpreted as an upper-bound estimate of year-over-year growth. Within the measured increase, New York SASB loans accounted for 64%.

Of the $18.3 billion originated during the 2026 period, $15.6 billion was SASB debt. SASB transactions are backed by one large loan or a related exposure to a single borrower rather than a diversified pool; conduit transactions generally pool smaller loans from multiple borrowers. Fourteen New York SASB loans account for 60% of the analyzed 2026 originated balance. Four properties alone account for $6.7 billion, or more than one-third of the analyzed private-label office CMBS market.

The difference between SASB and conduit lending is also visible in debt yield, calculated as net cash flow divided by the original loan balance. A lower debt yield means that a lender is providing more debt for each dollar of property cash flow. Among urban office loans in the analyzed sample, the median debt yield at origination was 9.5% for SASB loans and 15.6% for conduit loans. Using the unrounded medians, that equates to $10.48 and $6.42 of debt, respectively, for every dollar of net cash flow, which is a 63% difference. Among New York urban office loans, the corresponding median debt yields for SASB and conduit loans were 9.1% and 17.5%, respectively, or $11.04 and $5.73 per dollar of net cash flow, which is a 93% difference. These comparisons are descriptive, however: SASB and conduit loans differ materially in size and collateral composition, so the gap should not be interpreted as an apples-to-apples measure of underwriting aggressiveness.

Table 1: Urban Office Loans at Origination, Conduit Versus SASB

 Source: Trepp. as of August 2026. Based on private-label CMBS office loans originated from Jan. 1 through Aug. 4, 2026. Debt per dollar of net cash flow is calculated using the inverse of the unrounded median debt yield.

The Two Deal Types Finance Different Types of Office Properties

The collateral mix helps explain why the debt-yield comparison is not apples to apples. Urban offices account for 82.8% of SASB balance but only 30.3% of conduit balance, while suburban offices account for 60.9% of conduit balance and just 0.4% of SASB balance. Excluding other office subtypes, 99.5% of SASB balance is urban, compared with 33.2% of conduit balance. Size also differs sharply: the median SASB office loan originated during the period was $411.2 million, nearly 11 times the $38.0 million median for conduit loans.

The largest urban office loan originated during the period was the $1.8 billion financing of 9 West 57th Street, which was securitized in NYC 2026-9W57. That loan alone is more than twice the $0.8 billion balance of the entire urban conduit sample.

Table 2: 2026 Office CMBS Originations by Deal Type

Source: Trepp. Figures reflect private-label CMBS office loans originated from Jan. 1 through Aug. 4, 2026. Percentages may not sum to 100% because of rounding.

The Bottom Line

Among outstanding, non-defeased loans in the analyzed universe, private-label office CMBS origination volume through Aug. 4 was 25% higher than the comparable 2025 total. That estimate is an upper bound because the older cohort excludes loans that have since been repaid or defeased. Fourteen New York SASB loans account for 60% of the 2026 originated balance, while New York SASB loans account for 64% of the measured year-over-year increase. Four properties alone represent more than one-third of the 2026 total.

Urban office SASB loans also carry substantially lower median debt yields at origination than urban conduit loans, meaning they receive more debt per dollar of current cash flow. That gap should be interpreted cautiously because the two samples differ materially in loan size, collateral composition, property quality, and sponsor profile. The key test will be whether subsequently reported net cash flow supports the initial underwriting as these loans season.

Compliments of Trepp – a Premium Member of the EACCNY