Plan a family debt payoff with extra payments.
Debt payoff time follows from the amortisation formula, and it is highly non-linear in the payment. The reason is that interest is charged on the balance: at 18.9% APR, a 14,000 dollar balance accrues about 220 dollars of interest in the first month, so a 320 payment reduces the principal by only 100. Adding 150 dollars a month more than doubles the principal reduction, which is why a modest extra payment cuts years rather than months from the term. Two things to watch: if the payment does not exceed the monthly interest the balance never clears, and minimum payments on revolving credit usually fall as the balance does, which extends the term far beyond this calculation unless you hold the payment fixed.
Family Debt Payoff Plan
Monthly rate = APR / 1200; months = -ln(1 - rate x balance / payment) / ln(1 + rate); interest = payment x months - balance
General information, not financial advice. Actual payoff depends on your card or loan terms, fees, and whether the minimum payment recalculates — check your agreement and consider a free debt advice service if repayments are unaffordable.
Because the minimum payment is mostly interest. On a 14,000 balance at 18.9%, the first 220 dollars of any payment is interest — everything above that attacks the principal directly.
Highest rate minimises total interest. Smallest balance first clears accounts faster and sustains motivation. Both work; the avalanche is cheaper, the snowball is more often finished.