/

15 vs. 30 Year Mortgage Comparison

Compare a 15-year and a 30-year mortgage side-by-side — payments, total interest, real amortization, and the hidden opportunity-cost math of investing the payment difference.

Instant results Private — runs in your browser Updated October 2026

USALive

Refreshed daily from Freddie Mac PMMS (weekly survey) · data as of October 15, 2026

30yr Fixed
7.40%
15yr Fixed
6.71%

UKUpdated monthly

Updated monthly from Bank of England (IADB) · latest data September 30, 2026

BoE Bank Rate3.75%

2yr Fixed (75% LTV)
5.13%
5yr Fixed (75% LTV)
4.98%
Standard Variable
6.58%

Euro areaUpdated monthly

Updated monthly from ECB Data Portal · latest data August 2026

ECB Deposit Rate2.50%

Avg new home loan (ECB MIR)
3.60%
12M Euribor (2026-09 avg)
3.25%

AUSUpdated monthly

Updated monthly from Reserve Bank of Australia (F5/F1.1) · latest data September 30, 2026

Standard Variable
8.77%
Discounted Variable
6.80%
3yr Fixed
7.02%

CANReference

Reference figure (hand-reviewed June 2026) — not auto-fetched

BoC Rate2.75%

5yr Fixed
5.54%
Variable
5.95%

Rates shown are national averages for reference only. Actual rates vary by lender, credit score, and LTV. US 30/15-yr figures come from the Freddie Mac PMMS public dataset. UK (Bank of England), Euro area (ECB) and Australia (RBA) figures come from official statistics that publish monthly, so they lag by several weeks; each card shows its own latest period. If a source can't be reached, the card keeps the last figures it fetched successfully. Canada is a reference figure only. Countries without one credible national benchmark (e.g. India, where lender rates span roughly 7%–12%+) are intentionally not shown.

Inputs

Loan amount

15-year rate

30-year rate

Investment return (30 + invest diff)

Interest saved by 15-year

$285,603.80

15-yr payment $2,953.50 vs 30-yr payment $2,270.09 — difference $683.41/mo

15-yr payment

$2,953.50

30-yr payment

$2,270.09

Monthly difference

$683.41

15-yr total interest

$181,629.80

30-yr total interest

$467,233.60

15-yr total cost

$531,629.80

30-yr total cost

$817,233.60

Wealth @ y30 — 15-yr + invest

$936,147.79

Wealth @ y30 — 30-yr + invest diff

$617,121.17

Which wealth path wins at year 30?

Based on 7% investment return: 15-year + then invest ends with $936,147.79 vs $617,121.17 — a gap of $319,026.63.

How it works

We compute the standard amortizing payment for each term and rate, then simulate both schedules month-by-month for the full 30 years and track:

15-yr path: loan is paid off at year 15, then the freed-up 15-yr payment is invested for another 15 years.
30-yr path: pay the lower 30-yr payment, and invest the monthly difference for the first 15 years, then let it grow for 15 more.

At year 30 both paths are debt-free — the winner is whichever ends with more invested wealth. Total interest still matters (it's a guaranteed saving), but this shows the full picture.

Frequently asked questions

Why is the 15-year rate lower?

Shorter loans carry less duration risk, so lenders typically price them 0.5–0.75% below 30-year rates.

Is a 15-year always better?

It saves enormous interest but demands a much bigger payment. If that crowds out emergency savings, 401(k) match, or IRA contributions, the 30-year is usually the smarter overall play.

Can I mimic a 15-year on a 30-year loan?

Yes — pay extra principal each month equal to (15-yr − 30-yr payment) and you'll match the 15-yr payoff while keeping the flexibility to drop back to the lower required payment.

What does 'invest the difference' assume?

That every month you pay the 30-yr's lower payment and invest the difference at your assumed return. This is only a real advantage if you'll actually invest it consistently.

Do 15-year loans have prepayment penalties?

Almost never on modern conforming loans — but always confirm with your specific lender.

Which term is most popular in the US?

30-year fixed dominates (~85%+ of purchase originations) because it minimizes the required monthly payment.