Why compound interest is important

February 09, 2021

Harness the power of compounding for long-term investing success.

Albert Einstein once called compound interest the most powerful force in the universe. Here’s how it works, what affects it, and how to make the most of it in your investing strategy.

What is compound interest?

When you make an investment, you hope it earns a return. For instance, a $1,000 investment might return 7% in year one, for a total return of $70. The next year, you could reinvest the $70 and make an investment of $1,070. If that investment once again returned 7%, you’d get a total return of $74.90. The $70 in returns from year one compounded to give you an extra $4.90.

Therein lies your opportunity: The return on your investment generates its own return. Said more simply, through the power of compounding, even your interest earns interest. This effect can grow stronger with time. 


Imagine the return after five years if you invest more than $1,000 initially. Or if you invest for 30 years instead of five.

Why is compounding important?

Compound interest has the most impact in long-term investing, since its effects increase as time goes on.

Using the previous numbers, let’s say you withdrew your returns every year, instead of letting them compound in the investment account. In our example, that would be a withdrawal of $70 each year.

Five years later, you would have earned $350 in withdrawals instead of $403 in compound interest (assuming a 7% return each year). After 10 years total, taking the returns each year without compounding would earn you $700. Letting your investment earn compound interest would result in a gain of $968.

If you’re investing for a long-term goal like retirement, the way returns can compound significantly over time means you can do more with less.

How to take advantage of compounding

The single biggest way to benefit from compounding is to start investing as early as possible. If you want to retire with a certain amount of money, the earlier you start, the less you would have to invest initially. You may even be able to set aside less as you age and put more money toward other goals. The longer your investments have to compound, the greater the impact.

Here’s another illustration (again using a yearly return of 7% as an example – see graphic below): Imagine you’re planning to retire at 70. If you invested your first $1,000 at age 40 and held it for 30 years, you’d have just over $7,613. If you had started at age 20, you’d have more than $29,458 at age 70 — even if you never added another penny .

If you were starting at age 40 and wanted that same $29,000 in retirement (assuming the same rate of return) you’d have to invest roughly $3,900 to start.


Graphic is hypothetical and for illustrative purposes only.

 

The good news is even if you didn’t start early, you still have more time now than you will next year, or the year after that. The more you can put away today, the greater the opportunity for compounding to work.

 

Want to learn more about investing? No matter your level of investment experience, this guide to investing can help you take your knowledge to the next level.

Related content

Investment strategies by age

How to start investing to build wealth

5 questions to help you determine your investment risk tolerance

Robo advisors vs. financial advisors: How are they different?

Start a Roth IRA for kids

Investing myths: Separating fact from fiction in investing

Guide for investing

5 financial benefits of investing in a vacation home

7 diversification strategies for your investment portfolio

Do your investments match your financial goals?

Can fantasy football make you a better investor?

4 major asset classes explained

ETF vs. mutual fund: What’s the difference?

Effects of inflation on investments

4 times to consider rebalancing your portfolio

A beginner's guide to investing

Why compound interest is important

What types of agency accounts are available for investors?

What type of investor are you?

Understanding yield vs. return

Saving vs. investing: What's the difference?

How much money do I need to start investing?

How do interest rates affect investments?

Disclosures

Start of disclosure content

Investment and insurance products and services including annuities are:
Not a deposit • Not FDIC insured • May lose value • Not bank guaranteed • Not insured by any federal government agency.

U.S. Wealth Management – U.S. Bank is a marketing logo for U.S. Bank.

The information provided represents the opinion of U.S. Bank. This is not intended to be a forecast of future events or guarantee of future results.

U.S. Bank and its representatives do not provide tax or legal advice. Your tax and financial situation is unique. You should consult your tax and/or legal advisor for advice and information concerning your particular situation.

U.S. Bank does not offer insurance products but may refer you to an affiliated or third party insurance provider.