Add a fixed extra dollar amount to the principal portion of your mortgage every month. Even $100–$200 extra per month can cut years off a 30-year loan.
Anyone with any room in their budget. The impact is real even at small amounts.
Decide on a fixed extra amount you can afford comfortably each month.
When making your payment, add the extra amount and label it 'apply to principal only.'
Confirm on your statement that the extra is reducing principal — not being held.
Increase the amount any time your income grows.