DSCR

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Debt Service Coverage Ratio (DSCR) in Commercial Mortgage Lending

What Is DSCR?

Debt Service Coverage Ratio (DSCR) measures a property’s ability to generate enough income to cover its annual loan payments.

In simple terms, DSCR answers one critical lender question:

Does this property produce enough cash flow to safely pay the mortgage?

DSCR is one of the most important underwriting metrics in commercial real estate lending and is used to:

  • Approve or decline loans

  • Size loan amounts

  • Price interest rates

  • Assess risk

The DSCR Formula

DSCR = Net Operating Income (NOI) ÷ Annual Debt Service

Definitions:

  • NOI (Net Operating Income):
    Property income after operating expenses, before debt service and taxes

  • Annual Debt Service:
    Total principal + interest payments required in one year

How to Interpret DSCR

DSCR Meaning
1.00x Break-even (no margin for error)
1.10x Very tight, high risk
1.20x Marginal but acceptable for some lenders
1.25x Common bank & agency minimum
1.35x+ Strong coverage, lower risk

Example:

  • DSCR of 1.25x means the property generates 25% more income than required to cover debt payments.

Real DSCR Example (Underwriting Math)

Property Financials

  • Underwritten NOI: $400,000

Loan Terms

  • Loan amount: $4,500,000

  • Interest rate: 6.50%

  • Amortization: 30 years

  • Annual debt service: ~$342,000

DSCR Calculation

DSCR = $400,000 ÷ $342,000 = 1.17x

Result:

❌ Does NOT meet a 1.25x DSCR requirement

The lender will not approve this loan at the requested amount.

How Lenders Use DSCR to Size Loans

Lenders often work backward from DSCR to determine the maximum loan amount.

Example:

  • Required DSCR: 1.25x

  • NOI: $400,000

Maximum allowable debt service =
$400,000 ÷ 1.25 = $320,000

The loan amount is then sized so annual payments do not exceed $320,000.

This is why strong NOI is more important than property value in commercial lending.

Typical DSCR Requirements by Lender Type

Lender Type Typical DSCR
Banks / Credit Unions 1.20x – 1.30x
Agency (Fannie / Freddie) ~1.25x
CMBS 1.25x+
Life Companies 1.30x+
Private / Bridge 1.00x – 1.15x
Debt Funds Case-by-case

NOI vs DSCR (Common Broker Mistake)

  • NOI measures property performance

  • DSCR measures loan safety

A property can have strong NOI but still fail DSCR if:

  • The loan amount is too high

  • Interest rates increase

  • Amortization is too short

How Interest Rates Affect DSCR

As rates increase:

  • Debt service increases

  • DSCR decreases

Example:

  • NOI: $400,000

Rate Annual Debt DSCR
6.00% $310,000 1.29x
7.25% $355,000 1.13x

Many deals fail DSCR not because of bad properties, but because of rate movement.

Interest-Only Periods & DSCR

Interest-only (IO) payments reduce annual debt service, which:

  • Improves DSCR

  • Allows higher leverage

  • Increases lender risk

Some lenders:

  • Underwrite DSCR to amortizing payments, even if IO is offered

  • Allow IO only if DSCR remains acceptable after IO ends

DSCR vs Loan-to-Value (LTV)

Commercial loans are constrained by both:

Metric Measures
DSCR Cash flow strength
LTV Collateral risk

A loan must typically satisfy both:

  • Minimum DSCR

  • Maximum LTV

Whichever is more restrictive controls the loan size.

Common DSCR Red Flags for Brokers

  • DSCR only works on seller-provided NOI

  • DSCR relies on pro forma rent increases

  • DSCR fails under realistic interest rates

  • DSCR barely clears lender minimums

  • DSCR collapses after normalization

Best Practices for Commercial Mortgage Brokers

  • Always calculate DSCR before submitting to lenders

  • Use underwritten NOI, not seller NOI

  • Stress-test DSCR at higher rates

  • Understand each lender’s DSCR tolerance

  • Explain DSCR limitations to borrowers early

Broker Rule of Thumb

If the deal only works at today’s rate and perfect assumptions, it’s not a financeable deal.