You can find the answer by using an online calculator like the
Early Mortgage Payoff Calculator at TimeValue software
I used the calculator myself to generate some example numbers below.
For a $100,000 loan the number of years it will take to pay off an original 30 year mortgage based on making extra monthly payments of $100 to $600 :
4% | 5% | |
$100 | 21.6 | 21.3 |
$200 | 17 | 16.75 |
$300 | 14.1 | 13.8 |
$400 | 12 | 11.8 |
$500 | 10.5 | 10.3 |
$600 | 9.3 | 9.2 |
Roughly speaking if you pay an extra 50% on your mortgage monthly then it will cut your loan to about 15 years.
Doubling your payment will cut it down to about 10 years.
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