The Rent That Doesn’t Count: How Lenders Underwrite In-Place vs. Mark-to-Market, Percentage Rent, and Other “Non-Contract” Income

The Structural Paradox of Non-Contract Revenue

Commercial real estate generates income streams that exist in practice but not on paper. A retail tenant pays a percentage of sales above a base rent threshold. An in-place tenant occupies space at below-market rates because the lease was signed in a softer market. A property owner collects parking fees, CAM charges, or utility pass-throughs that are technically "other income" rather than rental revenue. A lender must decide whether to count these streams in the debt service coverage calculation, and if so, how much haircut to apply. This decision reveals a fundamental structural tension in commercial real estate credit: the gap between what happens in practice and what survives underwriting scrutiny.

The tension is not new. Over decades of cycles, lenders have discovered that non-contract income is the first revenue stream to vanish when a property enters stress. Percentage rent evaporates when sales decline. In-place rent becomes a political battleground during refinancing if market rents have fallen. CAM reconciliations become disputes. The result is a persistent conservative bias: lenders increasingly require explicit lease language, historical performance data, or explicit guarantees before counting non-contract income toward debt service.

In-Place Rent: The Market Rent Problem Inverted

In-place rent is the opposite of market rent. It is the rent a tenant actually pays today, locked into a lease that was signed months or years ago. If market rents have risen, in-place rent is a liability disguised as income. If market rents have fallen, in-place rent is an asset. Lenders must model the property's cash flow assuming the current tenant base and their existing lease rates, then reconcile that number against what the market would pay for the same space.

The structural problem: in-place rent is backward-looking. A lender underwriting a value-add or repositioning deal assumes the sponsor will eventually mark rents to market. But during the hold period, the property is stuck with in-place tenants on in-place leases. Debt service must be covered from day one, not five years from now when the rent roll has turned over. This creates a forced conservatism. A lender will typically underwrite in-place rent at 100 percent of the current lease rate, but will apply a haircut to any assumed rent growth until the lease rolls or the tenant renews.

The historical pattern is clear: lenders who assumed aggressive in-place rent growth during booms discovered that tenants either failed to renew at higher rates, or the market itself had softened by the time renewal arrived. The structural constraint is tenant behavior, not lender pessimism. A tenant with a below-market lease has no incentive to renegotiate upward. A tenant with an above-market lease will vacate or demand concessions. Lenders learned to model in-place rent conservatively, applying explicit lease-expiration schedules and renewal assumptions tied to trailing market comps rather than forward projections.

Percentage Rent: The Sales Volatility Problem

Percentage rent is pure volatility. A tenant pays a base rent plus a percentage of gross sales above a negotiated threshold. In strong sales years, percentage rent can represent 5 to 20 percent of total tenant rent. In weak years, it vanishes entirely. Yet on the lease, it looks like committed income.

The structural constraint is sales performance, which is not contractual. A tenant cannot be forced to generate sales; the percentage rent clause only captures what sales actually occur. Lenders have learned to treat percentage rent as bonus cash flow, not foundational debt service. The underwriting approach is consistent: apply a historical average or trailing percentage rent contribution, then apply a haircut for volatility. A lender might count 50 to 75 percent of trailing percentage rent in the DSCR, depending on the property type, tenant diversification, and historical stability.

The pattern repeats across cycles. Retail properties that looked strong on percentage rent during consumer-spending booms saw that income collapse during recessions. Lenders who had underwritten percentage rent as stable income discovered it was the first casualty of tenant stress. The structural response has been to reduce reliance on percentage rent for debt service coverage, and to require explicit historical documentation or third-party sales verification before counting it at all.

CAM, Utilities, and Other "Other Income": The Collection Problem

CAM reconciliations, utility pass-throughs, parking fees, and miscellaneous tenant reimbursements are technically "other income." They appear on the proforma and are counted in the underwriting. But they are the most fragile revenue streams in a property's cash flow.

The structural constraint is enforcement. A property owner can pass CAM charges to tenants, but only if the lease language permits it and only if the tenants have cash flow to pay them. During stress periods, tenants dispute CAM charges, contest reconciliations, or simply fail to pay. Parking fees decline when occupancy or foot traffic falls. Utility pass-throughs depend on meter accuracy and tenant cooperation. Lenders have learned that "other income" is the last claim on tenant cash flow, and the first to be deferred or forgiven during workout negotiations.

The underwriting response: lenders increasingly require explicit historical documentation of other income, applied as a percentage of trailing collections rather than as a forecast. A property that collected 95 percent of calculated CAM charges over three years might underwrite CAM at 85 percent of projected charges. Properties with weak collection histories see CAM underwritten at 50 to 75 percent of calculated amounts, or excluded entirely from debt service coverage.

The Structural Conservative Bias: Why Non-Contract Income Keeps Shrinking in Underwriting

Over decades, lenders have converged on a structural principle: non-contract income is real in theory but fragile in practice. The underwriting bias has shifted systematically from accepting non-contract income at full value to requiring explicit haircuts, documentation, and guarantees. This is not lender pessimism; it is the accumulated institutional memory of cycles.

The pattern is clear. In-place rent is underwritten conservatively because tenant renewal behavior is uncertain. Percentage rent is underwritten with heavy haircuts because sales volatility is structural. CAM and other income is underwritten at collection rates, not calculated amounts, because enforcement is weak during stress. Each of these constraints is not temporary; they recur because they are embedded in the nature of the income stream itself.

The result is a long-term structural tightening of non-contract income treatment. Lenders are increasingly requiring that debt service be covered by base rent alone, with non-contract income treated as upside or reserve funding. This shifts the underwriting burden onto the lease itself: the base rent must be sufficient to cover debt service under conservative assumptions, and any non-contract income is bonus cash flow that strengthens the deal but is not foundational to its survival.

What I'm watching next

• The extent to which lenders will require explicit historical documentation of non-contract income before counting it in DSCR, and whether this becomes a standard underwriting gate or remains discretionary by lender.
• How retail and hospitality properties will adjust underwriting assumptions for percentage rent and other variable income streams as consumer spending patterns become less predictable and lease structures evolve.
• Whether portfolio-level covenants will begin to isolate non-contract income separately from base rent in DSCR calculations, creating tiered debt service coverage requirements that reflect the structural fragility of these streams.