In an analysis on his blog, Financially SimpleGoodbread used national averages for these six parameters to compare different scenarios between investing and paying off a home loan early. When pressed for a rule of thumb, he offered two:. Homeowners need to maintain liquidity. If you have a financial emergency, cash reserves are essential. Homeowners who pour every dime into paying off their mortgage early might not have a cash cushion. Mortgage interest is inexpensive. Because the mortgage is secured by the value of the home, interest rates are much cheaper than for credit cards and personal loans — and the interest you pay is tax deductible.