DSCR answers a simple but unforgiving question: does the rental property generate enough net operating income to cover its debt payments? In 2026, with Portugal's average gross rental yield at 4.29% according to Global Property Guide, this test matters because gross rent often looks better than the financed cash flow.

Key takeaway: A DSCR of 1.25x means the property generates 25% more operating income than it needs to pay the annual mortgage. Below 1.00x, rent does not cover the debt.

What is DSCR?

In real estate, DSCR means Debt Service Coverage Ratio. It compares NOI, or net operating income, with annual debt service. NOI is rent after vacancy and operating costs, but before mortgage payments and income tax.

That makes DSCR different from rental yield. Yield measures return. DSCR measures financial resilience. A property can have a decent yield and still have a weak DSCR if the loan is too large, the term is too short, or the interest rate is too high.

What is the DSCR formula?

DSCR = NOI / Annual debt service NOI = annual rent − vacancy − operating costs. Debt service = annual principal + interest payments.

In 2026, the ECB deposit facility rate is 2.25% from 17 June, down from 3.00% in December 2024. Lower reference rates help mortgage payments, but investors still need to test the deal with conservative debt assumptions.

Portugal worked example

Assume a €250,000 Lisbon apartment with €1,500 monthly rent, 5% vacancy, €2,800 annual operating costs, and a €187,500 mortgage.

Line itemValue
Gross annual rent€18,000
Vacancy at 5%−€900
Operating costs−€2,800
NOI€14,300
Annual mortgage payments€11,400
DSCR1.25x

The most useful part of DSCR is not the base case. It is the stress test. If vacancy rises to 10% or the interest rate resets higher, the same deal can move from healthy to fragile quickly.

What is a good DSCR?

≥ 1.25xHealthy debt coverageGood margin for vacancy and repairs
1.00–1.25xThin but positiveNeeds careful stress testing
< 1.00xNegative coverageRent does not pay the debt

How can investors improve DSCR?

There are five levers: negotiate a lower price, increase the down payment, extend the loan term, reduce operating costs, or increase rent through a credible renovation. The cleanest lever is usually price, because it improves the loan size without relying on optimistic rent assumptions.

Run the numbers: use the free DSCR calculator to test loan amount, interest rate, vacancy, and operating costs before making an offer.

Sources

  • Global Property Guide, Portugal Rental Yields, retrieved 2026-06-19, https://www.globalpropertyguide.com/europe/portugal/rental-yields
  • European Central Bank, Key ECB Interest Rates, retrieved 2026-06-19, https://www.ecb.europa.eu/stats/policy_and_exchange_rates/key_ecb_interest_rates/html/index.en.html