Net Operating Income Calculator for Rental Property

Net operating income (NOI) shows how much income a rental property produces from normal operations before financing, income taxes, depreciation, and certain capital costs. It is one of the most useful building blocks in rental-property analysis because cap rate, debt-service analysis, and many investment comparisons begin with a realistic NOI.

The basic formula is:

NOI = Effective Rental Income − Operating Expenses

This page is a planning and recordkeeping guide, not tax, lending, appraisal, or investment advice.

Quick NOI calculator

Use these three steps:

1. Add annual rental income and other recurring property income.
2. Subtract a realistic vacancy/credit-loss allowance where appropriate.
3. Subtract normal annual operating expenses.

The result is the property’s annual net operating income.

Example NOI calculation

Assume a rental property produces:

• scheduled annual rent: $30,000;
• other recurring income: $600;
• vacancy allowance: $1,800;
• property tax: $3,000;
• insurance: $1,200;
• maintenance: $2,000;
• property management: $2,400;
• owner-paid utilities and other operating costs: $1,100.

Effective income is $28,800. Operating expenses total $9,700.

NOI = $28,800 − $9,700 = $19,100 per year.

What counts as rental income?

Start with recurring income generated by the property. Depending on the property, this may include base rent, parking, storage, laundry, pet rent, or other lawful recurring charges.

Use actual lease and payment records when available rather than assuming every scheduled dollar is collected.

Why vacancy belongs in the calculation

A property that is vacant for part of the year does not produce the same operating income as a fully occupied property. A realistic NOI model therefore accounts for expected vacancy or credit loss.

If you already use actual collected annual income, do not subtract the same vacancy loss twice. The model should be internally consistent.

What counts as an operating expense?

Common operating expenses include:

• property taxes;
• landlord insurance;
• property management fees;
• routine repairs and maintenance;
• owner-paid water, gas, electricity, trash, or internet where applicable;
• landscaping and snow removal;
• HOA or community costs where appropriate;
• pest control;
• routine administrative or operating costs.

Use categories that match the actual property rather than copying a generic list.

What is normally excluded from NOI?

For standard real-estate analysis, NOI is usually calculated before:

• mortgage principal and interest;
• income taxes;
• depreciation;
• investor-specific financing costs;
• major capital expenditures treated separately from normal operations.

This is why two buyers can calculate the same NOI for a property even when they use different loans.

NOI is not the same as cash flow

If NOI is $19,100 and annual mortgage debt service is $13,000, the property does not produce $19,100 of pre-tax cash flow.

A simplified cash-flow view would begin with:

Pre-tax cash flow = NOI − debt service − other non-operating cash items in your model

For monthly tracking after purchase, see Monthly Rental Property Cash Flow Tracker.

NOI is not the same as taxable rental income

Tax accounting uses its own rules for deductible expenses, depreciation, interest, capital improvements, personal use, and other items. NOI is an operating-analysis metric, not a tax-return line that should be copied blindly into a filing.

For U.S. tax recordkeeping, use current IRS guidance and professional advice where needed.

NOI and cap rate

Cap rate uses NOI as the numerator:

Cap Rate = NOI ÷ Property Value × 100

If NOI is wrong, cap rate is wrong. That is why operating-expense completeness matters more than producing an attractive percentage.

Use our Cap Rate Calculator for the next step.

NOI and rental property ROI

ROI analysis is broader. It can add financing, actual cash invested, cash flow, appreciation assumptions, principal paydown, sale proceeds, and other factors.

Use Rental Property ROI Calculator when you want the wider investment view.

Use annualized expenses carefully

Some bills are monthly, some quarterly, and others annual. Convert everything to the same period before calculating NOI.

For example, $125 per month in owner-paid utilities equals $1,500 per year. A $1,200 annual insurance premium equals $100 per month if you are building a monthly model.

Do not ignore irregular maintenance

A property can look unusually profitable in a year with few repairs. Review several years of maintenance history where available and decide whether a recurring maintenance allowance or reserve assumption is appropriate for planning.

Use the Landlord Maintenance Log to preserve actual repair history.

Capital improvements require separate attention

A new roof, HVAC replacement, major renovation, or structural project can consume substantial cash but is not the same as ordinary recurring maintenance. Keep capital work visible separately so the NOI calculation does not hide future cash needs.

NOI checklist

• scheduled rent verified;
• other recurring income included;
• vacancy handled consistently;
• property taxes included;
• insurance included;
• management included where relevant;
• maintenance included;
• owner-paid utilities included;
• debt service excluded;
• depreciation excluded;
• capital expenditures reviewed separately;
• all figures converted to the same annual period.

Improve NOI estimates with actual records

Before purchase, NOI is largely a forecast. After ownership, replace assumptions with real rent, vacancy, tax, insurance, maintenance, management, and utility data.

Use Rental Property Income & Expense Log and Rental Property Annual Expense Summary to create that history.

Where the Property Management Binder fits

The Property Management Binder helps organize the property records behind NOI: maintenance, vendors, insurance references, inspections, improvements, assets, and recurring operating information.

Frequently asked questions

What is the NOI formula?

NOI equals effective property income minus normal operating expenses.

Does NOI include mortgage payments?

No. Standard NOI is calculated before debt service.

Does NOI include depreciation?

No. Depreciation is a tax-accounting concept and is normally excluded from operating NOI.