$100/Month Extra on $300,000 Mortgage — Saves $69,338
Adding $100/month extra to a $300,000 mortgage at 7% saves $69,338 in interest and pays off 50 months early. Free calculator.
Frequently asked questions
How do extra payments help my mortgage?
Extra payments go directly to principal, reducing the balance on which interest accrues. This shortens the loan term and can save a significant amount in total interest over the life of the loan.
Should I make extra payments or invest that money?
It depends on your mortgage rate versus expected investment returns. Paying down a high-rate mortgage is a guaranteed return, while investing may earn more but carries risk. This calculator shows the interest saved so you can compare.
Is a monthly extra payment or one large lump sum better?
Both reduce principal, but timing matters: a lump sum early saves more interest because it cuts the balance sooner, while regular monthly extras build up steadily. The earlier the payment, the more interest it saves.