Updated September 2, 2026
Quick answer
DSCR is net operating income divided by annual debt service. A property producing $60,000 in net operating income against $50,000 of annual mortgage payments has a DSCR of 1.20 — it earns 20% more than it owes. Most lenders want at least 1.00, and commonly 1.20 to 1.25, so the arithmetic is worth doing before you apply rather than after.
The Formula
Every DSCR lender uses the same two-part equation:
DSCR = Net Operating Income ÷ Annual Debt Service
The elegance is also the trap. Both halves look obvious and neither is. Two underwriters handed the same property routinely produce different ratios, because they disagree about what belongs in each half — not about how to divide.
A ratio of 1.00 means the property exactly covers its debt. Below 1.00 it does not, and the shortfall comes out of your pocket every month. Above 1.00 there is a cushion, and the size of that cushion is what you are really negotiating.
What Counts as Net Operating Income
Net operating income is gross rental income minus operating expenses, before any mortgage payment. The mortgage is excluded deliberately: putting it in both halves would make the ratio meaningless.
What underwriters typically include as expenses:
- Property taxes — at the reassessed figure after your purchase, not the seller's current bill
- Insurance — at a bound quote, not last year's premium
- HOA dues where they apply
- Property management — commonly underwritten at a percentage of gross rent even when you self-manage
- Vacancy allowance — a deduction for the weeks the unit sits empty between tenants
- Maintenance and reserves on many programs
What does not belong: your mortgage payment, capital improvements, depreciation, and your own labour. Depreciation catches people out most often, because it is the single biggest line on many Schedule Es and it is a tax concept, not a cash one.
What Counts as Debt Service
Debt service is twelve months of payments on the loan being underwritten. Whether that means principal and interest only, or the full PITI figure, is the most consequential difference between programs.
| What the denominator includes | Effect on the ratio | Where you see it |
|---|---|---|
| Principal + interest only | Highest ratio | Some portfolio programs; taxes and insurance are then usually caught in the expense side instead |
| PITI — principal, interest, taxes, insurance | Lower ratio | The common convention on single-family rentals |
| PITIA — PITI plus HOA dues | Lowest ratio | Condos and any property with an association |
Ask which convention a lender uses before comparing two quotes. The same property can present as 1.25 under one definition and below 1.00 under another, and neither underwriter has done anything wrong.
A Worked Example
Take a single-family rental bought for $300,000, renting at $2,400 a month, financed with a $225,000 loan.
| Line | Monthly | Annual |
|---|---|---|
| Gross rent | $2,400 | $28,800 |
| Less vacancy allowance (5%) | −$120 | −$1,440 |
| Less property management (8%) | −$192 | −$2,304 |
| Less maintenance reserve | −$120 | −$1,440 |
| Net operating income | $1,968 | $23,616 |
| Principal & interest | $1,480 | $17,760 |
| Taxes | $310 | $3,720 |
| Insurance | $135 | $1,620 |
| Annual debt service (PITI) | $1,925 | $23,100 |
$23,616 ÷ $23,100 = 1.02. The property clears its debt, but only just. On a program wanting 1.20 this file does not work as structured — and the fix is arithmetic, not persuasion: a larger down payment, a longer amortization, or a different property.
Notice how thin the margin is. A $200-a-month miss on the insurance quote is enough to push this below 1.00.
Where the Ratio Usually Breaks
In practice, four things move a DSCR calculation more than anything else:
- Reassessed property taxes. Buyers budget the seller's tax bill. In states that reassess on sale, the real number can be substantially higher, and it lands entirely in the denominator.
- Insurance quotes. In coastal and wildfire markets premiums have moved sharply. A stale estimate is the most common reason a file that penciled at application fails at underwriting.
- Management fees you did not plan to pay. Many programs impute a management cost whether or not you use a manager.
- Optimistic rent. Underwriters generally take the lower of the lease and the appraiser's market rent opinion, so an above-market lease does not lift the ratio.
Run your own numbers with the reassessed tax figure and a bound insurance quote before you apply. It is the cheapest way to find out whether a deal works. Our DSCR calculator takes the same inputs an underwriter uses.
How to Improve a Ratio That Falls Short
A DSCR below the program minimum is a structuring problem, and it has a small number of levers:
- Increase the down payment. A smaller loan means smaller debt service, and this is the most direct lever there is.
- Extend the amortization. A longer schedule lowers the monthly payment and lifts the ratio, at the cost of more total interest.
- Consider an interest-only period where a program offers one. It reduces debt service during the interest-only term, which some lenders will underwrite to.
- Buy down the rate. Points paid at closing lower the payment and can lift the ratio over a threshold.
- Challenge the expense assumptions with evidence — a bound insurance quote below the underwriter's estimate is a legitimate, documentable correction.
What does not help: a strong personal balance sheet. That is the point of a DSCR loan, and it cuts both ways. See DSCR loan requirements for the thresholds each of these has to clear.
Frequently Asked Questions
What is a good DSCR for a rental property?
1.20 to 1.25 is comfortable on most programs, and 1.00 is the common floor — at 1.00 the property exactly covers its debt with nothing spare. Some lenders will go below 1.00 with compensating factors such as a larger down payment or reserves, and price accordingly.
Does DSCR include taxes and insurance?
It depends on the program, and this is the most consequential difference between two DSCR quotes. Many single-family rental programs use PITI — principal, interest, taxes and insurance — and condos usually add HOA dues to make PITIA. Others use principal and interest only and account for taxes and insurance as operating expenses instead. Ask before you compare.
Is depreciation included in the DSCR calculation?
No. Depreciation is a tax deduction, not a cash expense, so it is excluded from net operating income. This surprises owners who read their Schedule E and see depreciation as the largest line on the page.
Can you get a DSCR loan below 1.0?
Sometimes. Programs exist for ratios under 1.00, and occasionally with no ratio test at all, but they carry higher rates, larger down payments, or reserve requirements. The shortfall is real: below 1.00 the property does not cover its own debt and you fund the difference every month.
What rent do underwriters use if my lease is above market?
Generally the lower of the two. Underwriters compare the signed lease against the appraiser's market rent opinion, usually a Form 1007 rent schedule, and take the conservative figure. An above-market lease does not lift the ratio, though it does help the property perform in reality.
Sources & Further Reading
- IRS Publication 527: Residential Rental Property — The federal definition of rental income and deductible expenses - the same schedule an underwriter reads when your return is on file.
- Federal Reserve Senior Loan Officer Opinion Survey — Quarterly survey of bank lending standards, including commercial real estate. The public record of whether underwriting is tightening.
- U.S. Census Bureau Housing Vacancy Survey — Quarterly rental vacancy rates by region - the public check on whether a market rent assumption is realistic.
Figures above describe ranges commonly seen across DSCR lenders and reflect published guidance as of the date on this page. Confirm current terms with the cited source or your lender before acting.