Finance May 12, 2026 3 min read

Rent vs. Buy Calculator — Which Option Is Actually Cheaper for You?

O
OIYO Editorial Contributor

How do you really decide between renting and buying?

The question “should I rent or buy?” can’t be answered just by comparing monthly rent to a mortgage payment. The real answer depends on opportunity cost — what else you could do with the money tied up in a down payment or security deposit.

Locking $80,000 into a down payment means giving up the returns you could have earned investing that money elsewhere. That foregone return is called the opportunity cost, and it’s the key number most rent-vs-buy comparisons leave out.


The Core Formulas

True cost of buying

Down payment × expected annual return ÷ 12 = monthly opportunity cost on down payment
Plus: mortgage payment + property taxes + insurance + maintenance

Example: 400,000home,400,000 home, 80,000 down (20%), 7% mortgage rate, assuming 5% annual return on invested capital

  • Monthly mortgage (P&I): ~$2,128
  • Opportunity cost of down payment: 80,000×580,000 × 5% ÷ 12 = **333/month**
  • Property tax (~1.1% annually): ~$367/month
  • Insurance + maintenance estimate: ~$300/month
  • Total true monthly cost: ~$3,128

True cost of renting

Security deposit opportunity cost + monthly rent

Example: 3,000securitydeposit,3,000 security deposit, 2,500/month rent

  • Security deposit opportunity cost: 3,000×53,000 × 5% ÷ 12 = **12.50/month**
  • Total true monthly cost: $2,512.50/month

Compare Both Options with the Calculator

Enter your local home price, rent, down payment amount, mortgage rate, and expected investment return to see a direct comparison of true monthly costs.

Rent vs Monthly Comparison

Housing Cost Optimization

Compare housing costs considering opportunity cost and interest rates.

Jeonse

Monthly Opp. Cost

666,667

Monthly Rent

Monthly Total Cost

1,066,667

Jeonse is Better

Monthly cost difference

400,000

Per Month


When Buying Tends to Win

  • You plan to stay in the area for 5+ years (enough time for transaction costs to amortize)
  • Local rent-to-price ratios are high (rent is expensive relative to purchase price)
  • Mortgage rates are low relative to expected property appreciation
  • You value stability and have reliable income

When Renting Tends to Win

  • You have high-return investment opportunities for your down payment capital
  • You plan to move within 3–5 years
  • Home prices are inflated relative to rents (high price-to-rent ratio)
  • You want to avoid the risks of homeownership (repairs, market downturns)

Rent vs. Buy at a Glance

FactorRentingBuying
Upfront capital requiredLow (deposit only)High (down payment + closing costs)
Monthly fixed costsRent paymentMortgage + taxes + insurance
Opportunity costLowHigh (down payment tied up)
Financial riskLowerMarket risk, maintenance costs
Tax benefitsPossible deductions (state-dependent)Mortgage interest deduction (if itemizing)

The Mortgage Interest Deduction — What It’s Worth Today

US homeowners who itemize deductions can deduct mortgage interest paid each year. However, since the 2017 Tax Cuts and Jobs Act roughly doubled the standard deduction, most middle-income homeowners no longer benefit from itemizing.

  • Standard deduction (2024): 14,600(single)/14,600 (single) / 29,200 (married filing jointly)
  • Worth itemizing if: mortgage interest + state/local taxes + other deductions exceed the standard deduction
  • Example: 400,000mortgageat7400,000 mortgage at 7% = ~27,800 interest in year one. Add 5,000inpropertytaxes=5,000 in property taxes = 32,800 total — just above the married standard deduction.

Factor this into your true-cost comparison for a complete picture.


Conclusion

The rent-vs-buy decision is not just a numbers question — it involves opportunity cost, your risk tolerance, life plans, and tax situation. Use the calculator above with your actual numbers to find the answer that fits your life, not just the headlines.

O

OIYO Editorial

Content Editor

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