What this page is solving for
A DSCR loan is underwritten against the property rather than the borrower, so the question a lender is answering is narrow: does the rent cover the loan payment with enough margin to survive a bad month. Debt service coverage ratio is that margin expressed as a number. Divide the rent the lender is willing to count by the full monthly housing obligation, and a result of 1.00 means the rent exactly covers it, above 1.00 means there is cushion, and below 1.00 means the property cannot pay for itself on the lender's own arithmetic.
This page runs that calculation two ways. It tells you the ratio a given purchase price and down payment produce, and it solves the problem backwards — holding the rent, rate and term fixed, it reports the largest loan that still clears your lender's minimum, and the purchase price that loan implies. Our article on DSCR loans covers what ratios lenders tend to ask for and where these loans fit; this page is about operating the arithmetic.
Why the ratio is measured against PITIA, not the mortgage payment
The denominator here is PITIA — principal, interest, taxes, insurance and association dues — not the principal-and-interest figure a mortgage calculator reports. This matters more than it sounds. Taxes and insurance are obligations that arrive whether or not the property is rented, and a ratio built on principal and interest alone would make every deal look stronger than it is, with the error growing in exactly the markets where tax burdens are heaviest. Two properties with identical rent and identical loan payments can land on opposite sides of a lender's cutoff purely on the tax line.
Enter taxes and insurance as annual figures; the page divides them to a monthly basis itself. HOA dues are entered monthly because that is how they are usually billed.
Reading the example this page loads with
The default values describe a deal that does not qualify, which makes them more instructive than a tidy one. These numbers are illustrative — a teaching example, not market data for any particular city.
| Input | Value |
|---|
| Purchase price · down payment | $265,000 · 25% |
| Monthly market rent | $2,300 |
| Lender's rent haircut | 75% |
| Rate · amortization | 7.75% · 30 yrs |
| Taxes · insurance (annual) | $3,100 · $1,500 |
| Lender's minimum DSCR | 1.15 |
A 25% down payment on $265,000 leaves a loan of $198,750, which at 7.75% over thirty years costs $1,424 a month in principal and interest. Add $258 of taxes and $125 of insurance and the PITIA figure is $1,807. Against that, the lender counts 75% of the $2,300 rent, or $1,725 of qualifying rent. Dividing one by the other gives a DSCR of 0.95 — below 1.00, so on the lender's measure the rent does not cover the obligation at all, and well short of the 1.15 minimum entered.
The backward solve puts a number on the gap. At a 1.15 minimum, the most principal and interest this rent supports is $1,117 a month, which at the same rate and term is a loan of $155,869 — a shortfall of $42,881 against the loan actually being requested. Holding the 25% down payment constant, that loan implies a purchase price of about $207,826. Alternatively, at the $265,000 price the rent would need to reach roughly $2,771 to clear 1.15, roughly 20% above the rent assumed. Neither of those is a small adjustment, and that is the finding: this is not a deal that needs a slightly better rate.
The rent haircut, and why it is the field to get right
The haircut is the share of market rent the lender will count. At 75%, a quarter of the rent is set aside before the ratio is calculated, which is the lender's way of building in vacancy and operating costs without itemizing them. The field matters because it moves the result more than almost anything else on the page: at 100% the same example produces a DSCR of 1.27 and passes comfortably, while at 75% it produces 0.95 and fails. The deal did not change. The assumption did.
Practice varies between lenders and between loan programs, so this is a figure to confirm rather than assume. Some count the full market rent, some use the lesser of the in-place lease and an appraiser's market rent opinion, and some apply a fixed factor like the one defaulted here. Ask before you model, because a number pulled from the wrong program will give you a confident answer to the wrong question.
Why a DSCR loan skips the income paperwork
The reason these loans ask for rent rather than tax returns is regulatory as much as commercial. The federal mortgage servicing and settlement rules under RESPA, codified at 12 CFR part 1024, exempt from coverage an extension of credit made "primarily for a business, commercial, or agricultural purpose," a definition the rule borrows from Regulation Z at 12 CFR 1026.3(a)(1). A loan on a property bought to rent out is ordinarily business-purpose credit, so it falls outside the consumer-mortgage framework and the income verification machinery that framework requires.
Two things follow that are worth holding onto. The exemption attaches to the actual purpose of the loan, not to what a product is called, so occupying the property yourself changes the analysis rather than simply breaching a contract term. And the consumer protections that come with that framework are what you are stepping outside of — the disclosure timelines, the servicing-error procedures, the rules on escrow handling. The trade for a faster, income-free approval is a thinner regulatory floor underneath it.
What a passing ratio does not tell you
A DSCR above the minimum means the lender is satisfied. It does not mean the property makes money. PITIA contains no management fee, no maintenance, no capital expenditure reserve and no vacancy allowance beyond whatever is implied by the haircut, so a property can clear the ratio and still produce negative cash flow once those lines are counted honestly. Raise the haircut in the example above to 100% and the deal passes at 1.27 while the underlying economics are entirely unchanged.
Treat this page as the financing test and the single-family rental analyzer as the investment test; a deal worth doing has to survive both. The failure mode worth avoiding is using an approval as evidence that the numbers work, because the lender is measuring whether they will be repaid, which is a different question from whether you will be paid.
Changing the inputs sensibly
Three levers move the ratio and they are not equally honest. A larger down payment works and is fully within your control, but it is capital that stops earning elsewhere, and it improves the ratio by shrinking the loan rather than by improving the property. A longer amortization lowers the monthly payment and lifts the ratio while increasing total interest paid — real, though it buys qualification rather than performance. A lower price is the lever with the most room, which is what the max price figure quantifies.
The lever to be careful with is rent. It is the only input where optimism is invisible, and because the ratio is a straight division, every dollar of overstated rent passes through to the result undiluted. Start from comparable rents you can point at; our guide on where to find your numbers covers which public sources to use. It is also worth running the ratio at a rate somewhat above today's quote, since rates can move between an accepted offer and a closing and a deal that only clears at the quoted rate has no margin for that.