Quick answer
Divide the property’s gross monthly rent by its full monthly housing payment: principal and interest plus one-twelfth of annual taxes and insurance plus any monthly HOA dues. A result above 1.00 means rent covers the payment; below 1.00 means it does not. Use a real tax bill, a real insurance quote and a rate you enter yourself, because small input errors move the ratio more than people expect.
The formula
DSCR = monthly rent ÷ monthly debt service. That is all. The skill is in getting the two inputs right, and in remembering what the result does and does not tell you.
Monthly debt service is often shortened to PITIA: principal, interest, taxes, insurance and association dues. Some files add flood insurance or a ground-rent payment where they apply. Everything is expressed as a monthly figure, so annual bills are divided by twelve.
Step 1: Pin down the rent
For a property that is already leased, start with the monthly rent on the signed lease. For a purchase or a vacant unit, the number that usually matters is the appraiser’s estimate of market rent, which appears on a rent schedule attached to the appraisal. Before you have an appraisal, use a conservative estimate based on comparable rentals that are actually leased, not just listed.
For a 2-4 unit property, add every unit’s rent together. For a short-term rental, the approach varies by wholesale lender, so treat any projection cautiously until we confirm how your program measures income.
Step 2: Calculate principal and interest
Principal and interest depend on three numbers: the loan amount, the interest rate and the term. The standard amortization formula is:
Payment = L × r ÷ (1 − (1 + r)^−n)
where L is the loan amount, r is the annual rate divided by twelve (as a decimal), and n is the number of monthly payments. Our calculator applies this formula for you. We deliberately leave the rate field empty: enter a rate you have been quoted or one you want to stress-test. We do not publish or suggest rates, because pricing depends on your full file and changes over time.
If your program is interest-only for an initial period, the payment during that period is simply the loan amount times the monthly rate. Some wholesale lenders calculate DSCR on the interest-only payment and some on the fully amortizing payment, so it is worth running both.
Step 3: Add taxes, insurance and dues
This is where most do-it-yourself calculations go wrong. A few habits help:
- Use the actual tax bill, and ask whether a purchase will trigger a reassessment
- Get a landlord insurance quote for the specific address rather than guessing
- For condos and planned communities, use the exact monthly dues and ask about upcoming special assessments
- Include flood insurance if the property is in a designated flood zone
Divide the annual tax and insurance amounts by twelve and add them, along with monthly HOA dues, to principal and interest. That total is your monthly debt service.
Step 4: Divide and interpret
Let us walk through an example with made-up round numbers, purely to show the arithmetic. Suppose a single-family rental leases for $2,400 a month. Principal and interest at whatever rate you entered come to $1,500. Taxes are $3,600 a year ($300 a month), insurance is $1,200 a year ($100 a month), and there is no HOA. Monthly debt service is $1,500 + $300 + $100 = $1,900. DSCR is $2,400 ÷ $1,900, or about 1.26.
How should you read that? Here is the general way we frame it in the calculator. These are interpretive bands for planning, not program requirements:
- Below 1.00: the rent does not cover the payment. Some programs consider this, but options narrow and terms tend to be less favorable.
- Around 1.00 to 1.19: roughly break-even on paper. Workable with many programs, but there is little cushion for vacancy or repairs.
- 1.20 and above: comfortable coverage. This generally gives you the widest set of options and a healthier property.
Every wholesale lender sets its own thresholds, and the ratio is weighed alongside credit, leverage and reserves. Treat the bands as a conversation starter.
Common mistakes
- Using the listing’s advertised rent instead of what comparable homes actually lease for
- Forgetting HOA dues, or using last year’s dues after an increase
- Estimating insurance from a different property or an old policy
- Plugging in a rate from an article or an ad instead of your own quote
- Confusing DSCR with cash flow: a ratio above one can still mean negative cash flow after repairs and vacancy
Using the ratio to make decisions
Once you can calculate DSCR quickly, it becomes a planning tool. On a purchase, you can work backward: if the ratio is thin, how much more down payment would it take to improve it? On a cash-out refinance, you can find the loan amount where coverage stays comfortable. On a rate/term refinance, you can compare the ratio before and after to see whether the change is meaningful.
Our calculator updates as you type, so you can try several scenarios in a minute or two. When a scenario looks right, carry the numbers into the scenario builder, which packages everything into a summary you can send to a Loan Daddy loan specialist.
Frequently asked questions
Does DSCR include vacancy and maintenance?
Usually not. Most DSCR calculations compare gross rent to principal, interest, taxes, insurance and HOA dues only. Vacancy, repairs and management still affect your real cash flow.
Why is the rate field in the calculator empty?
Because pricing depends on your full scenario and changes over time. Enter a rate you have been quoted or one you want to test; we do not suggest or publish rates.
Is a higher DSCR always better?
Generally, more coverage means more options and more cushion. But the ratio is only one input; credit, leverage, reserves and the property all factor into the final decision.