The Power of Compound Interest (Guest post)
Monday, July 7th, 2008This is a guest post by Miranda Marquit. Miranda edits information about debt consolidation for DestroyDebt.com. She also writes on personal finances for the AllBusiness Personal Finance Corner.
One of the most interesting things in finances is the power of compound interest. Compound interest is interest that is not only charged on the principal (the amount you originally borrowed), but also on the unpaid interest that is accruing on the loan. Every time interest is charged, it is added to the principal, and for the next period you pay interest on the whole. Likewise, compound interest can be earned on an investment, such as a savings account. It can be a great burden, or it an be a great boon. It all depends on the money choices you make.
Compound interest can work against you
One of the most dramatic examples of how compound interest can work against you is the credit card. Every month your interest charges are added up and then tacked on to the principal. Pretty soon — especially if you only pay the minimum — you are paying interest on your interest, and barely reducing the principal at all. In fact, it is possible to pay back quadruple (or more!) what you originally borrowed when you are only paying the minimum. This is money that goes straight into someone else’s pocket without any benefit to you in exchange.
Other loans charge compound interest as well, but the credit card is the most common. It can also be one of the most difficult to get out of, since the interest rates charged are so high, and in some cases the interest is compounded daily.
Getting compound interest to work for you
Compound interest can be a great gift to you if, instead of spending money by carrying credit balances, you invest the money. A high yield savings account can get you a 3.75% annual yield. But if you look into certificates of deposit, you can get between 5.00% and 7.50%. And if you invest in a modest account, you can get average returns of between 8.00% and 11.00%. When you put money into interest bearing accounts (and there are money market checking accounts that you can earn money on as well), you essentially get paid for letting your money sit there. Compound interest represents free money. It works just like the loan in reverse. If you have $100 and an APY of 7.00%, at the end of the year, that free $7 you earn in interest is added to the principal. The next year you are earning 7.00% on $107, and that means you will get more in interest at the end of the second year, and so on.
Tips for helping compound interest work for you:
- Start immediately to invest your money (and a savings account or retirement account is an investment). The earlier you start, the more you will earn as compound interest works on your behalf. How much you start with isn’t as important as getting started.
- Let the money sit. This is easiest in a retirement account. Simply leave the money alone. It will gradually build up on itself as the interest you earn is added to the principal amount you invested — and then interest is earned on the new total.
- Add to your account regularly. While compound interest will work if you let it sit without adding anything, you can multiply the power of compoundinterest by making regular additions to your interest bearing accounts.
Consider your financial choices carefully. You want to be making compound interest work for you, rather than working against you.







