An IRA makes money through three mechanisms: interest or dividends on what you deposit, growth from investments you choose, and tax advantages that let your balance compound without being reduced by taxes each year

The money you put into an IRA doesn't sit idle. It goes into investments—usually stocks, bonds, mutual funds, or a mix of them—that generate returns. Those returns come as interest (from bonds or savings accounts), dividends (from stocks), or price increases (when the value of what you own goes up). In a regular taxable account, you'd owe taxes on those gains every year, which shrinks what's left to reinvest. In an IRA, you don't pay those taxes until you withdraw the money (or in a Roth IRA, often not at all), so your full balance keeps growing year after year.

The real power is compound growth: your money earns returns, those returns earn their own returns, and that cycle repeats for decades. A $5,000 deposit earning 7% annually becomes $5,350 after one year. That $5,350 then earns 7%, giving you $5,724.50. The second year's gain ($374.50) is larger than the first year's ($350) because you're earning returns on the returns. Over 30 years, that single $5,000 deposit can grow to roughly $38,000 without you adding another dollar—if the 7% average holds.

Key Takeaways

  • Your IRA balance grows through interest, dividends, and investment gains on the money you deposit and reinvest.
  • You don't pay taxes on those gains each year, so the full amount stays in the account to compound instead of being reduced by annual tax bills.
  • The longer your money sits in an IRA, the more compound growth works in your favor, which is why starting early matters more than starting with a large amount.
  • The actual return depends entirely on what investments you choose inside the IRA—a savings account earns less than a stock fund, but also carries less risk.

How Investment Returns Actually Work Inside an IRA

When you open an IRA, you choose where to hold it—usually at a bank, brokerage, or investment company. That institution doesn't give you the returns; the investments you buy do. If you buy a bond mutual fund, the bonds pay interest. If you buy stocks, companies may pay dividends and the stock price may rise. If you buy a money market fund, it earns a small interest rate. The IRA is just the container that holds these investments and shields the gains from annual taxes.

You control what goes into that container. A traditional IRA at a bank might hold only savings accounts or CDs, earning 4% to 5% annually (rates change). The same IRA at a brokerage might hold stock index funds averaging 10% annually over long periods, or bond funds averaging 3% to 4%. The difference in total growth is enormous. A $10,000 deposit earning 4% for 30 years becomes roughly $32,000. The same $10,000 earning 10% becomes roughly $175,000. That's why the investments you pick matter far more than the IRA type itself.

The Tax Advantage That Multiplies Your Growth

Outside an IRA, if you own stocks that pay dividends or mutual funds that distribute gains, you owe federal income tax on those earnings each year—even if you don't touch the money. That tax bill comes out of your pocket or reduces what you can reinvest. In a traditional IRA, you pay no tax on those gains until you withdraw. In a Roth IRA, you typically pay no tax on those gains ever. That difference compounds dramatically.

Imagine $50,000 earning 8% annually for 25 years. In a taxable account, if you're in the 24% federal tax bracket, you'd owe roughly $960 in taxes each year on the gains, leaving less to reinvest. After 25 years, you'd have roughly $290,000. The same $50,000 in a traditional IRA, with no annual tax drag, grows to roughly $342,000. The Roth grows the same way, but you owe zero tax when you withdraw. That extra $52,000 came entirely from not paying taxes along the way.

Why Starting Early Matters More Than Starting With a Large Amount

A 25-year-old who deposits $3,000 into an IRA earning 7% annually will have roughly $660,000 at age 65, assuming no additional deposits. A 45-year-old who deposits $10,000 into the same IRA will have roughly $76,000 at 65. The younger person added less money but had 40 years of compound growth. The older person added more but had only 20 years. Time is the most powerful variable in an IRA.

This is why financial advisors emphasize starting an IRA as soon as you have earned income, even with small amounts. A teenager who deposits $1,000 per year from age 16 to 25, then stops, will have more at 65 than someone who deposits $5,000 per year from age 35 to 65. The early deposits had 40 years to compound; the later ones had only 30. The math of compound growth heavily favors time over size.

What Happens to Your Money When You Withdraw

In a traditional IRA, withdrawals are taxed as ordinary income. If you withdraw $20,000 and you're in the 22% tax bracket, you owe roughly $4,400 in federal tax. That's the trade-off: you avoided taxes for decades, but you pay them when you take the money out. In a Roth IRA, you withdraw your contributions tax-free anytime, and you withdraw the growth tax-free after age 59½ if the account has been open at least five years. That's why a Roth is often better if you expect to be in a higher tax bracket in retirement.

Before age 59½, both types have withdrawal penalties—usually 10% of the amount withdrawn, plus income tax on the withdrawal. There are exceptions (first-time home purchase, disability, medical expenses), but they're narrow. The IRA is designed to stay untouched until retirement, which is another reason the long time horizon matters so much.

How Much Your IRA Can Grow Depends on Your Choices

The IRS sets annual contribution limits—for 2024, the limit is $7,000 per year for people under 50, and $8,000 for people 50 and older. Those limits reset each year. If you max out your IRA every year from age 25 to 65, you'll have deposited $280,000 (at the current limit, though it rises with inflation). If that money earns 7% annually, your balance at 65 will be roughly $1.2 million. If it earns only 4%, you'll have roughly $650,000. If it earns 10%, you'll have roughly $2.3 million.

The difference between 4% and 10% is the difference between your investment choices. A conservative portfolio of bonds and stable funds might earn 4% to 5%. A moderate portfolio of stocks and bonds might earn 6% to 8%. An aggressive portfolio of mostly stocks might earn 8% to 10% on average, with more ups and downs along the way. Younger people can usually afford to take more risk because they have decades to recover from downturns. Older people typically shift toward safer investments as they approach withdrawal.

The Role of Employer Matching in IRAs

If your employer offers a 401(k) or similar plan with matching contributions, that's assistance programs added to your account—and it compounds just like your own deposits. A 3% employer match on a $50,000 salary is $1,500 per year added by your employer. Over 30 years at 7% growth, that $1,500 annual match alone becomes roughly $180,000. Many people leave this money on the table by not contributing enough to get the full match.

A traditional IRA doesn't have employer matching—only workplace plans do. If your employer offers matching, prioritize contributing enough to capture it before maxing out an IRA. The may provide return on a match (usually 50% to 100% of what you contribute) beats any investment return in the market.

Frequently Asked Questions

Can I lose money in an IRA?

Yes, if your investments decline in value. If you own stocks or stock funds and the market drops 20%, your IRA balance drops 20%. The tax advantage doesn't protect you from investment losses. However, if you hold bonds, savings accounts, or CDs, your balance won't drop—it will just grow slowly. The risk depends on what you choose to hold inside the IRA.

Do I have to pick investments myself?

No. Many IRAs offer target-date funds that automatically adjust from stocks to bonds as you approach retirement. You pick your retirement year, and the fund handles the rest. Some IRAs also offer robo-advisors that build a portfolio based on your age and risk tolerance. You can also choose individual stocks or funds yourself if you want more control.

What if I don't add money every year?

Your balance still grows from the investments you own. If you deposit $5,000 once and never add another dollar, that $5,000 keeps earning returns for decades. Adding money every year accelerates growth, but even a single deposit compounds significantly over time. Many people add what they can afford each year rather than waiting to max out the limit.

Does the IRA growth count as income for taxes?

Not while the money is in the IRA. You don't report the annual gains on your tax return. In a traditional IRA, you pay tax only when you withdraw. In a Roth IRA, you typically pay no tax on the growth at all. That's the entire point of the tax shelter.

How do I know what return to expect?

Historical averages give a rough guide: stock funds have averaged around 10% annually over very long periods, bond funds around 4% to 5%, and savings accounts currently 4% to 5%. But past returns don't may provide future ones, and returns vary year to year. A financial advisor or your IRA provider can show you historical returns for specific funds you're considering.