Advanced Financial Tool

Offset Mortgage Calculator Dashboard

Calculate how much interest and time you can save on your mortgage by offsetting it with your savings. Discover how your savings can work harder for you by reducing your mortgage interest daily and shortening your loan term.

Mortgage Details

Configure your loan and offset savings

$50,000$2,000,000
1%15%
1 year40 years
$0$500,000
$0$5,000

Total Interest Saved

$306,307

Time Saved

8y 6m

Payoff Date

22 years

Standard Total Interest

$579,191

With Offset

$272,883

Pro Tip: Even a small monthly offset contribution can significantly reduce your total interest and shave years off your mortgage.

Mortgage Balance Over Time

$Principal
Start
Year 30
Standard Mortgage
With Offset

Interest Comparison

Standard Interest$579,191
With Offset
$272,883-53%

Standard Payment

$1,079,191

Offset Total

$772,883

Yearly Milestone Comparison

Comparing Standard vs Offset Balance

YearStandard BalanceOffset BalanceInterest Saved (Acc.)Savings Growth
Year 1$493,860$490,608+$3,252$56,000
Year 2$487,341$480,267+$7,074$62,000
Year 3$480,420$468,918+$11,502$68,000
Year 4$473,073$456,499+$16,573$74,000
Year 5$465,272$442,944+$22,328$80,000
Year 6$456,990$428,183+$28,807$86,000
Year 7$448,197$412,141+$36,055$92,000
Year 8$438,862$394,740+$44,121$98,000
Year 9$428,951$375,896+$53,055$104,000
Year 10$418,429$355,519+$62,910$110,000
Year 11$407,257$333,515+$73,742$116,000
Year 12$395,397$309,785+$85,613$122,000
Year 13$382,805$284,220+$98,585$128,000
Year 14$369,437$256,709+$112,729$134,000
Year 15$355,244$227,130+$128,114$140,000
Year 16$340,176$195,357+$144,819$146,000
Year 17$324,178$161,255+$162,923$152,000
Year 18$307,194$125,369+$181,825$158,000
Year 19$289,162$89,396+$199,766$164,000
Year 20$270,018$53,423+$216,595$170,000
Year 21$249,693$17,450+$232,243$176,000
Year 22$228,115Paid Off+$246,638$179,000
Year 23$205,205Paid Off+$259,702$179,000
Year 24$180,883Paid Off+$271,352$179,000
Year 25$155,060Paid Off+$281,503$179,000
Year 26$127,645Paid Off+$290,061$179,000
Year 27$98,539Paid Off+$296,928$179,000
Year 28$67,638Paid Off+$301,999$179,000
Year 29$34,831Paid Off+$305,165$179,000
Year 30$0Paid Off+$306,307$179,000

How it Works

Interest is calculated on the mortgage balance minus the linked savings balance. Unlike a standard savings account where you earn taxable interest, an offset account saves you mortgage interest which is effectively tax-free and usually calculated at the much higher mortgage rate.

The Logic

Effective Balance = Loan Principal - Offset Balance

Example Scenario

Mortgage: $500,000, Interest Rate: 6%, Offset Balance: $50,000 - Effective Balance = $500,000 - $50,000 = $450,000 - Monthly Interest (Standard) = 500,000 * (0.06/12) = $2,500 - Monthly Interest (Offset) = 450,000 * (0.06/12) = $2,250 - Monthly Saving = $250 Result: Higher principal reduction and faster loan payoff.

Knowledge Hub

Frequently Asked Questions

Q: How does an offset mortgage work?

An offset mortgage links your savings account to your mortgage. The balance in your savings is subtracted from the mortgage balance before interest is calculated, meaning you only pay interest on the difference.

Q: Do I still have access to my savings?

Yes, typically you can access your savings in an offset account just like a regular savings account. However, withdrawing money will increase the interest you pay on your mortgage.

Q: Can an offset mortgage shorten my loan term?

Yes! Because less of your monthly payment goes toward interest, more goes toward paying down the principal. This accelerates the repayment process and can shave years off your mortgage.

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Why Use Offset?

  • Tax Efficiency: Savings interest is usually taxable, but mortgage interest saved isn't.
  • Term Reduction: Paying less interest means your principal drops faster, shortening your loan.
  • Flexibility: Keep your cash for emergencies while still saving on mortgage interest.

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