How to Calculate Capitalization Rate (Cap Rate) for Real Estate

Capitalization Rate, commonly known as Cap Rate, is the single most critical metric used by commercial real estate investors, appraisers, and brokers to compare properties and estimate rate of return. It measures the unlevered yield of an asset over a one-year time horizon.

In simple terms, the Cap Rate tells you what your rate of return would be if you purchased a property entirely in cash, without using any debt (mortgage). Underwriting cap rates correctly is essential because it allows investors to normalize property valuations across different debt structures.

The Cap Rate Formula

Calculating a cap rate is straightforward. You divide the property's annual Net Operating Income (NOI) by its current Market Value (or purchase price).

Step 1: Calculate Net Operating Income (NOI)

The cap rate calculation is only as accurate as your Net Operating Income (NOI). NOI represents all the revenue generated by the property, minus its operating expenses.

1. Gross Potential Income (GPI)

Add up all rental income if the property were 100% occupied at market rates.

2. Vacancy and Credit Loss

Subtract an allowance for empty units or unpaid rent (typically 5% to 10% of GPI).

3. Other Income

Add secondary revenue streams like laundry facilities, parking fees, pet rent, or storage locker rentals. This yields the Effective Gross Income (EGI).

4. Operating Expenses

Subtract the costs required to run and maintain the property.

Asset Class Expense Ratio Rules of Thumb

Operating expenses vary dramatically based on the property type. When underwriting deals, real estate professionals rely on regional average Operating Expense Ratios (OER)—the percentage of gross income spent on operations:

A Practical Valuation Example

Suppose you are looking at a 10-unit apartment building:

• Asking Price: $1,500,000
• Annual Rental Income: $180,000
• Other Income (Laundry): $5,000
• Vacancy Rate: 5% ($9,000 loss)
• Annual Operating Expenses: $82,000 (management, taxes, insurance, repairs)

Let’s calculate the NOI:

Effective Gross Income (EGI) = $180,000 + $5,000 - $9,000 = $176,000 EGI

Net Operating Income (NOI) = $176,000 - $82,000 = $94,000 NOI

Now, we calculate the Cap Rate:

Cap Rate = ($94,000 / $1,500,000) × 100 = 6.27%

Buying this property cash yields a return of 6.27% on your capital.

What is a Good Cap Rate?

There is no single "good" cap rate. Cap rates are a reflection of risk:

• Low Cap Rates (4% – 5%): Typical for high-demand, low-risk areas (e.g., class-A apartments in coastal cities). These assets hold value but offer lower cash-flow returns.
• High Cap Rates (7% – 9%+): Found in higher-risk markets (e.g., class-C commercial buildings in rural regions or cities with declining populations). These assets cash-flow heavily but risk higher vacancy and little capital appreciation.