Is a 15-year mortgage always the cheaper option?
It is usually cheaper in total interest, but not always better overall. The higher required payment can reduce flexibility and make the household budget less resilient.
15 vs 30 Year Mortgage Calculator
Compare payment pressure, lender quotes, and lifetime interest before you lock in a mortgage term
Compare Term Scenarios
Use separate lender quotes for the 15-year and 30-year options.
$450,000
$75,000$2,000,000
20%
3%50%
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Decision rule
The 15-year path saves $276,707 in interest.
It also requires about $738 more each month. If that payment feels too tight, a 30-year mortgage with roughly $738 in extra principal can mimic much of the faster payoff while preserving flexibility.
15-year term
$3,624/mo
Includes $3,014 in principal and interest at 5.875%.
Total Interest
$182,453
Down Payment
$90,000
30-year term
$2,885/mo
Includes $2,275 in principal and interest at 6.5%.
Total Interest
$459,160
Down Payment
$90,000
What changes most
15-year vs 30-year tradeoff snapshot
Monthly Gap
$738
more each month for 15-year
Interest Saved
$276,707
if you choose the 15-year
30-Year Hybrid
$738
extra principal to mimic the shorter payment
About This Tool
Term comparison
Compare payment pressure against lifetime interest with real term quotes
Use separate 15-year and 30-year rates to see whether the lower-rate shorter term is worth the higher required payment for your situation.
Typical Use
About 1 minute
Best For
Buyers and refinancers deciding between lower required payments and faster payoff
Main Output
Side-by-side monthly payment and total interest comparison by term
Built Around
Standard mortgage math and planning assumptions
What to prepare
- Home price, down payment, and separate 15-year and 30-year mortgage rates
- Monthly taxes, insurance, and HOA assumptions for all-in payment context
What you get back
- Required payment difference between the two terms
- Estimated interest saved by choosing the shorter amortization path
Why trust this view
- Lets you model the fact that 15-year and 30-year quotes are often not the same rate
- Frames the decision as flexibility versus forced acceleration, not just total interest
- Useful for planning; lender pricing and qualification can still shift the real options
Source notes and methodology details are available on our references page.
15 vs 30Rate ComparisonTerm Choice
Industry-Standard Calculations
Our calculations follow the Truth in Lending Act (TILA) guidelines and use standard financial formulas employed by major lending institutions.
Monthly Payment Calculation
M = P[r(1+r)^n]/[(1+r)^n-1]Where M = monthly payment, P = principal loan amount, r = monthly interest rate, n = number of payments
Amortization Schedule
Standard declining balance methodEach payment is split between interest (calculated on remaining balance) and principal reduction
APR Estimation
Includes interest + fees over loan termAnnual Percentage Rate calculations include all financing charges as required by Truth in Lending Act (TILA)
About MortgageCalcMaster
Content is published under the MortgageCalcMaster editorial team workflow, currently led by the site operator, reviewed against public mortgage and consumer-finance sources, and updated when assumptions, formulas, or product behavior materially change.
Last reviewed: March 2026. All calculators and guides are intended for education and planning. They do not replace lender disclosures or advice from licensed professionals. Learn more about our editorial process
How to Use 15 vs 30 Year Mortgage Calculator
1
Enter the home price and down payment so both term options are evaluated on the same loan amount.
2
Use the actual 15-year and 30-year lender quotes if you have them. If not, start with your best estimate for each term.
3
Add monthly taxes, insurance, and HOA dues so the all-in payment comparison reflects the full housing budget.
4
Compare the monthly payment gap against the interest savings instead of choosing a term on instinct alone.
Key Terms Explained
- 15-Year Mortgage
- A shorter amortization term that usually has a higher required payment but lower lifetime interest.
- 30-Year Mortgage
- A longer amortization term that usually lowers the required payment and preserves more monthly flexibility.
- Monthly Gap
- How much more the 15-year option requires each month compared with the 30-year option.
- Equivalent Extra Principal
- The rough monthly extra payment needed on a 30-year loan to mimic the shorter required payment cadence.
Pro Tips
- If the 15-year payment works only when every month goes right, the 30-year option may be safer even if the interest line is larger.
- If you choose a 30-year for flexibility, decide in advance how much extra principal you will aim to send in stronger months.
- Re-run the comparison whenever rates change materially or when taxes, insurance, or HOA assumptions tighten the budget.
Important Note
This calculator provides estimates based on standard formulas. Actual loan terms may vary based on your credit score, lender policies, and market conditions. Always consult with a qualified mortgage professional before making financial decisions.
Related Guides
Use these guides to connect the term comparison to real household decision-making.
Guide
15 vs 30 Year Mortgage
Learn the real tradeoff between flexibility, interest cost, and required payment pressure.
Guide
How Mortgage Interest Works
See why the longer term compounds so much more interest over time.
Guide
Understanding Amortization
Understand how a shorter term shifts each payment toward principal faster.
Related Tools
Move from the term decision into the next calculators borrowers usually use.
FAQ
15 vs 30 Year Mortgage Calculator FAQ
These answers explain the assumptions behind the calculator so users can interpret the output with the right context.
Why does this calculator use two separate rates?
Because lenders often quote a lower rate for a 15-year mortgage than for a 30-year mortgage. Comparing them with one shared rate can hide the real tradeoff.
Can a 30-year mortgage still be part of a fast-payoff strategy?
Yes. Many borrowers choose the 30-year payment for flexibility and then add extra principal when cash flow allows.