Mortgage Offset Account Calculator
Compare with-offset vs without-offset scenarios on an Australian mortgage. See exact dollars of interest saved and how many years you can cut off your loan term.
Average balance held in the linked offset account; reduces the principal that accrues interest.
Annual cost hurdle
A constant-balance, one-year estimate. It is separate from the lifetime savings above.
Enter a no-offset loan rate (and any extra annual fee) to see the balance needed to cover the cost.
Not a lender recommendation. Savings-account returns, tax deductibility, switching costs and changes in principal or rates are outside this annual comparison. Example rates in this tool are hypothetical.
Use some offset cash: withdraw and rebuild
Scenario A leaves the offset untouched and does not pay for the purchase. Scenario B pays for it from the offset, then uses other household cash to rebuild the balance. The comparison shows the financing cost of B; the two scenarios do not have the same spending or household wealth.
Enter a withdrawal amount to compare taking cash out of the offset with leaving it there.
A per-repayment-period approximation: in each month the withdrawal comes out first, interest is charged on the loan balance less the offset, the contractual repayment is made, then the rebuild deposit goes in. Your lender's own calculation (for example on daily balances) will differ, so this will not match a loan statement. The rate, loan term and repayment are held the same in both scenarios. Not advice on tax deductibility, redraw, new borrowing or future rates.
Amortisation with offset applied
| Period | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| 1 | $3,062.34 | $582.34 | $2,480.00 | $499,417.66 |
| 2 | $3,062.34 | $585.35 | $2,476.99 | $498,832.30 |
| 3 | $3,062.34 | $588.38 | $2,473.97 | $498,243.92 |
| 4 | $3,062.34 | $591.42 | $2,470.93 | $497,652.51 |
| 5 | $3,062.34 | $594.47 | $2,467.87 | $497,058.03 |
| 6 | $3,062.34 | $597.55 | $2,464.80 | $496,460.49 |
| 7 | $3,062.34 | $600.63 | $2,461.71 | $495,859.85 |
| 8 | $3,062.34 | $603.74 | $2,458.61 | $495,256.12 |
| 9 | $3,062.34 | $606.85 | $2,455.49 | $494,649.26 |
| 10 | $3,062.34 | $609.99 | $2,452.35 | $494,039.27 |
| 11 | $3,062.34 | $613.14 | $2,449.20 | $493,426.13 |
| 12 | $3,062.34 | $616.31 | $2,446.04 | $492,809.82 |
| 324 | $3,062.34 | $3,062.34 | $0.00 | $14,167.01 |
| 325 | $3,062.34 | $3,062.34 | $0.00 | $11,104.67 |
| 326 | $3,062.34 | $3,062.34 | $0.00 | $8,042.32 |
| 327 | $3,062.34 | $3,062.34 | $0.00 | $4,979.98 |
| 328 | $3,062.34 | $3,062.34 | $0.00 | $1,917.63 |
| 329 | $1,917.63 | $1,917.63 | $0.00 | $0.00 |