Imagine you’re buying a house, and borrowing $200,000 to do it. What is the total cost of the loan? Well 6% of $200,000 is $12,000. But that’s just for the first year. Under a standard payment plan, you’ll end up paying $231,676 in interest – 116% of the original loan amount.

Let’s look at student loans next: The standard interest rate for a PLUS Loan is 8.5% APR. If you borrow $40,000 for college and are on a 20-year repayment plan, you’ll end up paying $43,311 in interest – 108% of the original loan amount.

Do you carry a balance on your credit card? Among American households with credit card debt, the average amount is about $11,000. At a typical 18% APR, if you start paying down your balance with $300 per month, it will take about 4 years, and you’ll pay $5,090 in interest – 46% of the original loan amount.

One more example: two-week “payday” loans usually cost about $15 for every $100 borrowed. So if you get a payday loan for $400, you’ll pay $60 in interest – 15% of the original loan amount.

See the pattern here? Long-term loans generally have lower annual interest rates. But over a few decades, even a low rate can really add up. The best strategy is to pay cash when you can, and only borrow when you need to. And if you have a little spare money at the end of the month, use it to get ahead on your bills and you’ll save big in the long run.

This chart compares the total costs of these different loan types: