An IRA itself does not earn interest — the investments inside it do

An Individual Retirement Account (IRA) is a container, not an investment. The money you put into an IRA earns returns based on what you choose to hold inside it: savings accounts, certificates of deposit (CDs), bonds, stocks, mutual funds, or other securities. The IRA is the tax-sheltered wrapper; the interest or growth comes from the specific investments you select.

If you open an IRA at a bank and leave the money in a non-interest-bearing checking account, it will not grow. If you buy a CD inside that IRA, it will earn the CD's stated rate. If you buy stock mutual funds, your return depends on how those funds perform. The IRA rules determine how much you can contribute each year and when you can withdraw without penalty; they do not determine what your money earns.

Key Takeaways

  • An IRA is a tax-advantaged account structure, not an investment itself — you choose what goes inside it and what it earns.
  • Common IRA investments include savings accounts (earning modest interest), CDs (earning fixed rates), bonds (earning coupon payments), and stock or bond mutual funds (earning variable returns).
  • The type of IRA (Traditional or Roth) affects how your earnings are taxed, but not how much they grow.
  • IRA contribution limits and withdrawal rules are set by the IRS, but the growth rate depends entirely on your investment choices inside the account.

What investments inside an IRA actually earn interest or returns

A savings account held inside an IRA earns interest at whatever rate your bank or credit union offers. These rates vary by institution and change over time; as of early 2024, IRA savings accounts at online banks typically earn between 4% and 5% annually, while rates at traditional brick-and-mortar banks are often lower. The interest is credited to your account and compounds, but you cannot withdraw it before age 59½ without paying a 10% early withdrawal penalty (with limited exceptions) plus income tax on the earnings.

Certificates of Deposit (CDs) in an IRA earn a fixed interest rate for a set term — typically three months to five years. The rate is locked in when you buy the CD. If you withdraw the money before the term ends, you pay an early withdrawal penalty to the CD issuer (separate from the IRA early withdrawal penalty). A one-year IRA CD might earn 4.5% to 5.5%, depending on the bank and the current rate environment.

Bonds and bond funds in an IRA earn interest payments (called coupon payments on individual bonds) or distributions from the fund. Individual bonds held to maturity return your principal plus all interest owed. Bond funds pay out interest monthly or quarterly, but their share price fluctuates with interest rate changes, so you can lose principal if you sell before rates stabilize.

Stock mutual funds and exchange-traded funds (ETFs) in an IRA do not earn interest in the traditional sense. They earn returns through price appreciation (the fund's value goes up) and dividends (companies pay shareholders). A stock fund's total return is the combination of these two. Returns are variable and can be negative in down markets.

How Traditional and Roth IRAs differ in how earnings are taxed

Both account types hold investments and allow those investments to grow, but the tax treatment of your earnings differs. In a Traditional IRA, your contributions may be tax-deductible in the year you make them (depending on your income and whether you have a workplace retirement plan). The earnings inside the account grow tax-deferred — you do not pay income tax on interest, dividends, or capital gains each year. You pay income tax on the full amount (contributions plus earnings) when you withdraw after age 59½.

In a Roth IRA, contributions are made with after-tax dollars, so you get no immediate deduction. However, earnings grow tax-free, and withdrawals after age 59½ are completely tax-free if the account has been open at least five years. This makes Roth accounts more valuable if you expect your earnings to be substantial or if you expect to be in a higher tax bracket in retirement.

The growth rate itself — how much interest a CD earns, how much a stock fund appreciates — is the same regardless of which IRA type holds it. The difference is in the taxes you owe on that growth.

Why the type of investment matters more than the IRA type

Your actual returns depend almost entirely on what you buy inside the IRA, not on the account structure itself. A Traditional IRA holding a 5% CD will earn 5% annually. A Roth IRA holding the same CD will also earn 5% annually. The Roth version avoids taxes on that 5%, but the 5% itself comes from the CD, not from the IRA label.

This is why investment choice is critical. A savings account earning 4.5% will grow much more slowly than a stock fund averaging 8% to 10% over decades. A bond fund earning 3% to 4% sits between the two. If you are young and have decades until retirement, a higher-growth investment (stocks or stock funds) typically builds more wealth, even though it carries more year-to-year volatility. If you are close to retirement, a mix of bonds and stocks (or a target-date fund that automatically shifts toward bonds) may suit you better.

How compound growth works inside an IRA

One major advantage of an IRA is that you do not pay taxes on earnings each year, so all of your interest and gains stay in the account and compound. If you earn $500 in interest on a $10,000 CD in a regular taxable account, you might owe $100 to $150 in taxes, leaving only $350 to $400 to reinvest. In an IRA, the full $500 stays in the account and earns interest next year.

Over 20 or 30 years, this tax deferral (or tax-free growth in a Roth) makes a significant difference. A $10,000 investment earning 6% annually grows to roughly $32,000 in 20 years inside an IRA with no annual tax drag. The same investment in a taxable account, assuming a 24% federal tax rate on earnings each year, grows to roughly $24,000. The IRA version is worth about $8,000 more — and that gap widens the longer the money sits.

Common mistakes: leaving money in cash or misunderstanding IRA limits

Many people open an IRA, contribute the maximum allowed, and then leave the money in a money market account or savings account earning 4% to 5%. This is safe but slow. If you have 30 years until retirement, a portfolio weighted toward stocks or stock funds historically builds significantly more wealth, even accounting for market downturns. The IRA structure protects you from taxes on those gains; it does not require you to choose low-growth investments.

Another common misunderstanding: the IRA contribution limit (currently $7,000 per year for those under 50, or $8,000 for those 50 and older, though these limits change periodically) is not a limit on how much your money can earn. You can contribute $7,000 once and let it grow to $50,000 or $100,000 over decades. The limit applies only to new contributions each year, not to the total balance or the earnings on that balance.

Frequently Asked Questions

Do I have to pick an investment when I open an IRA, or can I decide later?

You can open an IRA and leave the money in a cash account (savings or money market) while you decide. Many brokers and banks allow this. However, the longer you wait to invest in growth-oriented options, the less time compound growth has to work. If you are unsure what to buy, a target-date fund (which automatically adjusts from stocks to bonds as you approach retirement) is a simple starting point.

Can I move money between different investments inside my IRA without paying taxes?

Yes. Selling a CD and buying a stock fund inside the same IRA, or moving money from one investment to another, does not trigger taxes or penalties. The IRA tax protection applies to the account as a whole, not to individual investments within it. You can trade as often as you want without tax consequences.

What happens to IRA earnings if I withdraw money before age 59½?

You pay income tax on the full amount withdrawn (contributions plus earnings) plus a 10% early withdrawal penalty on the earnings portion. Some exceptions exist — first-time home purchase (up to $10,000 lifetime), disability, and a few others — but most early withdrawals are costly. This is why an IRA is best used for money you will not need until retirement.

Is a CD inside an IRA better than a stock fund for retirement savings?

It depends on your timeline and risk tolerance. A CD is predictable and safe but grows slowly. A stock fund is volatile but historically builds more wealth over 20+ years. Many people use a mix: bonds or CDs for money they will need soon, and stock funds for money they will not touch for a decade or more. A target-date fund does this automatically.

How do I know what interest rate or return to expect from an IRA investment?

For CDs and savings accounts, your bank publishes the rate upfront. For stock and bond funds, you can see historical returns on the fund company's website, but past performance does not may provide future results. A bond fund might show a 4% average annual return over the past 10 years; a stock fund might show 9%. These are guides, not promises. Your actual return depends on market conditions and when you buy and sell.