Comparison Guide7 min read

15 vs 30 Year Mortgage (Cost, Payment, and Break-Even Analysis)

The 15 vs 30 year mortgage comparison involves two distinct financial tradeoffs: a 15-year loan pays far less total interest and builds equity faster, but requires a monthly payment $600 to $900 higher than a 30-year loan on the same balance. That higher payment either saves you $200,000 to $300,000 in interest or costs you significant financial flexibility, depending on how you manage the difference.

This guide compares a $350,000 mortgage on each term side by side using real payment math, lifetime interest totals, and the investment opportunity cost of the payment difference. Use the BuyOrRent.ai calculator to model your specific loan balance and compare the two options.

15-year saves $264,960 in interest on a $350,000 loan

A 15-year mortgage at 6.0% on a $350,000 balance pays $181,720 in total interest. A 30-year at 6.5% pays $446,680. The 15-year saves $264,960 over the loan life and pays off the home in half the time.

The 15-year payment is $741/mo higher on the same balance

On a $350,000 loan, the 15-year payment is $2,954/mo versus $2,213/mo for the 30-year. That $741 monthly difference is the core tradeoff: pay more each month and eliminate interest, or keep flexibility and potentially invest the difference.

Investing the $741 difference at 7% grows to $884,000 in 30 years

If the 30-year borrower consistently invests $741 per month at 7% annual return, the portfolio reaches $884,000 after 30 years. This exceeds the $264,960 in interest savings from the 15-year loan by over $619,000. The investment path wins if returns exceed the mortgage rate.

15-year rates are typically 0.25% to 0.75% lower than 30-year rates

Lenders charge lower rates on 15-year loans because they carry less duration risk. The rate gap of 0.25% to 0.75% reduces the 15-year payment compared to what it would be at the 30-year rate, and amplifies the interest savings beyond what loan term alone produces.

Is a 15 Year Mortgage Worth It?

A 15-year mortgage is worth it when you have stable income that comfortably absorbs the higher payment, you want to be debt-free before retirement, and you do not have a disciplined plan to invest the monthly payment difference at a return that exceeds the mortgage rate. When mortgage rates are 6% to 7%, the investment return threshold to favor the 30-year is achievable but not guaranteed, making the 15-year a rational choice for conservative borrowers.

The 30-year mortgage provides more flexibility and potentially greater wealth if the payment difference is invested. See the break-even guide and hidden costs guide for the full cost picture of homeownership beyond the mortgage payment.

Who Should Compare a 15 vs 30 Year Mortgage?

This comparison is most relevant for buyers who have flexibility in down payment and monthly budget, and who want to understand the long-term cost difference before committing to a loan term. It is also useful for current homeowners considering refinancing from a 30-year to a 15-year loan.

You want to minimize total interest paid over the loan life

The 15-year loan eliminates $264,960 in interest on a $350,000 balance. Buyers who prioritize minimizing total cost of borrowing and can absorb the higher payment should strongly consider the 15-year loan, particularly when rates are elevated and the rate gap between terms is 0.5% or more.

You want to compare payment flexibility against interest savings

The 30-year loan's lower required payment provides a $741/month buffer. For buyers with variable income, self-employment, or uncertain near-term expenses, that buffer may be more valuable than the interest savings from the 15-year term.

You are refinancing and want to know if switching terms makes sense

Homeowners refinancing from a 30-year to a 15-year can significantly accelerate payoff and reduce interest, but must ensure the higher payment is sustainable at current income levels. The break-even on refinancing closing costs typically runs 18 to 36 months.

Why Loan Term Changes Total Cost

Loan term changes total cost because interest accrues on the remaining balance every month. A longer loan term means more months of interest charges on a balance that declines more slowly. Even at the same interest rate, doubling the loan term roughly doubles the total interest paid.

In simple terms, loan term means the length of repayment

In simple terms, loan term means the number of years over which you repay the mortgage. A 15-year term means 180 monthly payments. A 30-year term means 360 monthly payments. Each payment covers that month's interest charge plus a portion of the principal. The longer the term, the smaller each principal reduction, and the more months of interest you pay.

In practical terms, total cost refers to interest paid over time

In practical terms, total cost refers to the sum of all interest payments made over the life of the loan. On a $350,000 loan at 6.5%, you pay approximately $22,750 in interest in year one alone. By the end of 30 years, that loan's total interest reaches $446,680. The 15-year loan at 6.0% charges less interest per year (lower rate, faster balance reduction) and runs for only 15 years, producing $181,720 in total interest.

The calculator methodology covers how interest accumulation is modeled over different loan terms and how extra payments accelerate payoff.

Section 1

When a 15 Year Mortgage Makes More Sense

Your income is stable and the higher payment represents less than 25% of gross monthly income: On a $350,000 loan with a $2,954 monthly payment, you need gross income of approximately $11,800 per month ($141,600 per year) to keep the payment under 25% of income. Buyers with stable, predictable income at this level can sustainably absorb the higher payment without financial risk.
You plan to hold the home into retirement and want it paid off before stopping work: A 30-year loan taken at age 40 pays off at age 70, deep into retirement. A 15-year loan taken at age 40 pays off at 55, before most retirement milestones. Eliminating housing debt before retirement significantly reduces the income needed to cover monthly expenses after stopping work.
You do not have a disciplined investment plan for the monthly payment difference: The 30-year loan only wins financially if the $741 monthly payment difference is actually invested at a return that exceeds the mortgage rate. Studies consistently show that most households do not maintain disciplined monthly investing at this level. For borrowers without a specific investment plan for the savings, the 15-year loan is often the better financial outcome in practice.

Section 2

When a 30 Year Mortgage Makes More Sense

You have other high-return investment opportunities above the mortgage rate: When mortgage rates are 6.5% and your investment portfolio earns 8% to 10% in diversified index funds or real estate, the math favors the 30-year loan. You borrow at 6.5% and earn 8% to 10% on the freed capital. This spread of 1.5% to 3.5% compounds significantly over 30 years.
The higher 15-year payment would deplete your emergency fund or limit retirement contributions: Financial stability requires liquid reserves. A buyer who stretches to the 15-year payment and holds no emergency fund faces serious risk if income drops unexpectedly. Similarly, maximizing 401(k) contributions up to employer match is almost always a better financial decision than paying down a low-rate mortgage aggressively.
Your income is variable or likely to change in the next 5 years: Commission income, self-employment income, or income from a spouse who plans to reduce work hours creates payment risk. The 30-year loan's lower required payment provides flexibility to scale back during lean periods while still making extra payments when income is strong.

Section 3

Worked Example: 15 vs 30 Year Payment and Interest

$350,000 loan. 15-year at 6.0% vs 30-year at 6.5%. Payment and lifetime interest table.

Item15-Year (6.0%)30-Year (6.5%)

Loan amount$350,000$350,000

Monthly P&I payment$2,954$2,213

Monthly payment difference$741 moreBaseline

Total payments made$531,720$796,680

Total interest paid$181,720$446,680

Interest savings (15-year)$264,960 lessBaseline

Equity at year 5$134,400$43,000

Equity at year 10$261,000$98,000

$741/mo invested at 7% for 30 yrsN/A$884,000

The 15-year borrower pays $264,960 less in total interest, which is the clearest argument for the shorter term. After 5 years, the 15-year borrower holds $134,400 in equity versus $43,000 for the 30-year borrower, a $91,400 equity advantage that grows each year. By year 15, the 15-year loan is paid off entirely and the borrower owns the home free and clear.

The 30-year case depends on the final row. If the 30-year borrower invests $741 per month at 7% annual return for the full 30 years, the portfolio reaches $884,000. That exceeds the $264,960 interest savings from the 15-year by $619,000. After the 30-year loan is paid off, the investor holds the $350,000 home free and clear plus an $884,000 investment portfolio, versus the 15-year borrower who owns the home and has had the extra $741/month available to invest only since year 15.

The critical assumption is whether you will actually invest $741 every month for 30 years at 7% returns. In practice, most households use the extra monthly cash for lifestyle expenses rather than systematic investing. For buyers who will not maintain that discipline, the 15-year loan delivers the better long-term financial outcome by forcing wealth accumulation through equity.

What Changes the Result Most?

The rate gap between 15 and 30 year loans

When the rate gap is 0.5% or more, the 15-year loan becomes even more attractive because it benefits from both the shorter term and the lower rate. When the gap narrows to 0.1% to 0.2%, the 15-year's advantage shrinks and the 30-year's flexibility becomes more compelling.

Whether you invest the payment difference

This is the most important variable. The 30-year loan only wins mathematically if the payment difference is consistently invested at a rate above the mortgage rate. Historically, stock market index funds return 7% to 10% annually, which exceeds most mortgage rates. But past performance does not guarantee future returns.

Your employment stability and income predictability

Variable income households benefit more from the 30-year payment's flexibility. Salary earners with stable, long-tenured employment and strong emergency funds can safely commit to the 15-year payment without meaningful risk of financial strain.

Proximity to retirement and housing cost in retirement

Buyers within 20 years of retirement who want housing costs eliminated before stopping work should weight the 15-year option heavily. The elimination of the mortgage payment in retirement reduces the income needed to maintain the same lifestyle, creating lasting financial security.

Run Your Scenario

Enter your loan amount, both rates, and investment return assumption to see your exact 15 vs 30 year payment, total interest, and wealth comparison.

Compare 15 vs 30 Year Mortgage

Frequently Asked Questions

Is a 15 year mortgage better than a 30 year?

A 15-year mortgage is better if your primary goal is minimizing total interest paid and you can comfortably afford the higher monthly payment. The 15-year loan on a $350,000 balance at 6.0% costs $2,954 per month in principal and interest and pays $181,720 in total interest. The 30-year at 6.5% costs $2,213 per month and pays $446,680 in total interest. The 15-year saves $264,960 over the loan life. However, if the $741 monthly difference would be invested at 7% for 30 years, it grows to $884,000, which exceeds the interest savings. The better choice depends on whether you will invest the payment difference and at what return.

How much interest do you save with a 15 year mortgage?

On a $350,000 loan, a 15-year mortgage at 6.0% saves approximately $264,960 in total interest compared to a 30-year loan at 6.5%. The savings scale with loan size. On a $500,000 loan, the interest savings exceed $378,000. The savings are also boosted by the lower interest rate that 15-year loans typically carry, usually 0.25% to 0.75% below 30-year rates, because lenders face less duration risk on shorter loans.

Is the higher payment worth it?

The higher 15-year payment is worth it when you have stable income that comfortably covers the larger amount, you want to pay off the home before retirement, or you do not have a disciplined plan to invest the monthly payment difference. It is not worth it when the payment creates financial stress, limits your emergency fund, or takes capital away from higher-return investments. At mortgage rates around 6% to 7%, the case for a 15-year depends heavily on whether your alternative use of the extra $700 to $900 per month earns a return above the mortgage rate.

Can you pay off a 30 year loan early?

Yes. A 30-year loan can be paid off early by making additional principal payments. One extra payment per year on a $350,000 loan at 6.5% cuts approximately 5 to 6 years off the loan term and saves roughly $70,000 to $80,000 in interest. This strategy gives you the flexibility of the lower required payment while still allowing aggressive payoff when cash flow permits. Most conventional loans have no prepayment penalty, allowing unlimited extra payments. Verify your loan terms before making extra payments.

Which loan is better for flexibility?

The 30-year mortgage offers significantly more financial flexibility. The required monthly payment is $741 lower on a $350,000 loan, which provides buffer during income disruptions, periods of high medical or childcare costs, or market downturns. A 30-year borrower can choose to pay like a 15-year borrower when cash flow is strong and scale back to the minimum payment during lean periods. The 15-year borrower is locked into the higher payment regardless of circumstances.

Methodology

All calculations use a $350,000 loan amount. 15-year scenario: 6.0% fixed rate, 180 payments, monthly P&I $2,954 using standard amortization formula, total interest $181,720. 30-year scenario: 6.5% fixed rate, 360 payments, monthly P&I $2,213, total interest $446,680. Interest savings: $446,680 - $181,720 = $264,960. Payment difference: $2,954 - $2,213 = $741/month. Investment scenario: $741/month invested at 7% nominal annual return for 360 months using future value of annuity formula = $884,000 (approximate). Equity at years 5 and 10 estimated from amortization schedule at each loan term. Opportunity cost of down payment not modeled in this comparison. Rate gap between 15 and 30 year loans modeled at 0.5%; actual gap varies by lender and market conditions. All assumptions are illustrative and not personalized advice. Actual rates and returns vary and are not guaranteed.

Editorial Note: This content is provided for informational and educational purposes only and does not constitute financial, tax, legal, mortgage, or real-estate advice. Housing decisions depend on local market conditions, personal finances, and property-specific factors. Consult qualified professionals before making financial decisions.