Economics
Debt Repayment
Quick fact
Making only the minimum payment on a $5,000 credit card balance at 18% APR can take over 20 years to pay off and cost more than $7,000 in interest alone.
Why this is interesting
You borrow money to buy something today, but why does it often feel like you're paying forever? The secret lies in how debt repayment actually works.
Read the full explanation
Understanding Debt Repayment
Imagine you lend a friend $100 and ask them to pay it back over 10 weeks. If you charge no interest, they'd simply give you $10 each week. That's like a zero-interest loan. But in real-world debt, lenders charge a fee for using their money—called interest. When you repay a loan, each payment first covers the interest that has accumulated, and only the remainder reduces the original amount you borrowed (the principal). This is why early payments mostly cover interest, leaving the principal barely touched. Over time, as the principal shrinks, the interest portion gets smaller, and more of your payment goes toward principal. This process is called amortization. If you only pay the minimum required on a credit card, you're often barely covering the interest, so the principal falls very slowly—making repayment drag on for years.
A deeper explanation
The mechanism that makes debt repayment challenging is compound interest working in reverse. When you borrow, interest accrues on the outstanding balance. If you don't pay off the entire interest each period, unpaid interest gets added to the principal, and future interest is calculated on that larger amount. This is how debt can snowball. Amortization schedules calculate each payment to fully repay the loan by the end of its term. But lenders design minimum payments to be low enough to keep you paying longer—maximizing their interest income. Understanding this reveals why paying just a little extra each month can slash years off your repayment time and save thousands. For example, adding $50 to a monthly car loan payment can cut the repayment period by a third. This principle applies to mortgages, student loans, and any installment debt. Debt repayment is not just about sending money each month; it's a strategic game of reducing principal faster than interest can grow.