Tools
Mortgage payoff vs. invest calculator
The calculator runs the scheduled mortgage payment, then either adds extra principal or invests that extra. Interest saved is the sure part. The investment balance depends entirely on the return you type in.
Arc · Published September 18, 2026 · Updated September 18, 2026
Assumptions
- Scheduled payment about $2,577 before the extra.
- The return is an assumption. The mortgage rate is the sure saving.
- Taxes and mortgage insurance are not modeled.
Interest saved by paying extra
$125,547
If you invest the extra
$0
Portfolio after the original term, assuming the return you entered.
If you pay extra, then invest
$330,732
Extra principal finishes ahead under this return.
The mortgage rate is treated as the after-tax rate you care about. If you do not itemize, that is usually the contract rate. The investment return is an assumption, not a projection Arc stands behind.
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Educational estimate only. Not tax, legal, or investment advice, and not a prediction of what your accounts will do. Methodology