Debt-Service Coverage Ratio Calculator

What the DSCR calculator does

The debt-service coverage ratio calculator tells you whether an income property earns enough to pay its own loan. It divides the property's annual net operating income by its annual debt service and returns the ratio, along with the cash surplus left after the loan is paid. You and any lender can read from it whether the rent carries the mortgage or whether you would need to top it up from other income.

DSCR is widely used in property investment and commercial lending because it involves no tax rules or market-specific assumptions. The same calculation works for an apartment in one country and an office building in another: enter two figures in any currency and the ratio means the same thing everywhere.

How the ratio works

Net operating income, the money left after running costs but before financing, goes on top. Annual debt service, the full year of principal and interest payments, goes underneath. Dividing the first by the second gives the coverage ratio.

A ratio of 1.0 is break-even: income exactly equals the loan payments. Above 1.0, the property produces more than it owes and the surplus is cash you keep each year. Below 1.0, the income falls short and the gap has to come from elsewhere, usually your own savings or salary. The ratio ignores what you paid and what you hope prices will do; it only measures the income against the debt.

Reading your result

If the calculator returns 1.4, the income covers the debt 1.4 times, leaving a 40% cushion. That cushion protects you when a tenant leaves, a boiler fails, or rates rise, and the larger it is, the more shocks the property can absorb before it starts costing you money.

The ratio gives the proportion and the surplus gives the amount. A property can look healthy on the ratio yet leave only a small surplus if the numbers are modest, so read both.

• Well above 1.0, the property supports itself with a comfortable margin, which is the position most lenders and investors want.
• Around 1.0 to 1.2, it covers the loan with little room for error; a rise in costs or a vacant month can tip it into the red.
• Below 1.0, the property cannot pay its own way and relies on outside money.

Why lenders care

For an investment or commercial mortgage, the lender lends against the property's income, and DSCR is how it measures that income against the repayment burden. Most lenders set a minimum, commonly around 1.20 to 1.25, and will not advance a loan that pushes the ratio below it.

For the lender, a cushion above 1.0 means the loan keeps being repaid if rents dip or expenses climb. For you, it prevents a loan so large that one bad quarter turns the investment into a monthly drain. Running the ratio before you apply shows whether a deal will clear the lender's bar, and how much you might need to change the loan size or the price.

Improving a weak ratio

Higher rent lifts net operating income directly, and so does cutting operating costs: a lower management fee or insurance premium flows straight through to the ratio. A larger deposit means a smaller loan and smaller payments. A longer loan term spreads the same balance over more years, reducing each year's payment and lifting the ratio, though it costs more interest over the life of the loan. Paying less for the same income improves every ratio at once, which is why disciplined investors let the required DSCR set the maximum price they will offer.

Adjust the two inputs to see how much extra deposit or lower price it takes to reach a lender's threshold.

Using DSCR alongside other measures

DSCR tests income against debt and nothing else. The capitalisation rate gives the return on the property's value regardless of financing, cash-on-cash return shows what your invested cash earns, and net operating income on its own shows earning power before any loan. A property can score well on one and poorly on another, so look at them together to judge whether it is priced well, earns a fair return, and can safely carry the debt you plan to put on it.

Test a deal before you commit, insist on a margin above 1.0 instead of relying on best-case rents, and use the ratio to set the largest loan and the highest price the income can support.

This article is general information only and is not financial advice.

About This DSCR Calculator

Use this DSCR calculator to get an instant estimate based on the figures you enter. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.