Calculator guide

Cash Flow Calculator

Monthly cash flow is the money left in your pocket each month after every expense and loan payment is covered. This guide shows exactly how it's calculated.

What the metric means

Monthly cash flow is the money left in your pocket each month after every expense and loan payment is covered. This guide shows exactly how it's calculated.

Formula

Monthly Cash Flow = Effective Gross Income − Operating Expenses − Monthly Debt Service

Where:

Effective Gross Income
Gross rent × (1 − vacancy rate)
Operating Expenses
Management, maintenance, CapEx reserves, taxes, and insurance
Monthly Debt Service
Principal and interest payment on the loan

Example:

  • Effective gross income = $1,980/month
  • Operating expenses = $780/month
  • Monthly debt service = $960/month
  • Step 1: Cash Flow = $1,980 − $780 − $960
  • Step 2: Cash Flow = $240/month

After paying all expenses and the mortgage, this property generates $240/month in spendable income — under current assumptions.

How DealPrism uses it

DealPrism recalculates cash flow anytime rent, vacancy, taxes, insurance, financing, or operating reserves change so investors can pressure-test the same deal quickly.

Common mistakes

  • Ignoring vacancy because the property is currently occupied.
  • Treating maintenance and CapEx like optional expenses.
  • Forgetting that higher leverage can turn a marginal deal negative.

Related FAQs

Analyze your own deal

See this metric in context with your purchase price, rent, expenses, and financing assumptions.

Analyze your own deal

DealPrism provides educational analysis based on available data and user assumptions. Results are estimates and may change if rent, taxes, insurance, financing, or other inputs are updated. This content is not financial, legal, tax, or investment advice.