Saving for retirement gives people a sense of security and makes them more confident in their future. However, most people don’t feel like they’ve put enough away for their post-work years.

According to a recent Pew Charitable Trust study, seven out of 10 retirees wish they had started saving for retirement earlier, and around half of Americans worry that they’ll run out of money in retirement.

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If you want to be among those who achieve financial security in retirement, you need to start planning now. Many people assume that they can rely solely on their 401(k) or individual retirement account to provide everything they need once they stop earning a paycheck, but that may not end up being the case.

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401(k) Plans and IRAs Can Erode Your Savings

Since both types of accounts are tax-deferred investments, you won’t be taxed until you make a withdrawal during retirement. This might seem like an advantage at first, but the potential for rising tax rates could mean that your tax bill will be higher in the future than it is now.

Think about it this way: You’re contributing money to your 401(k) or IRA in today’s dollars. If inflation goes up in the future, your purchasing power will be reduced, making your money worth less then than it’s worth now. In addition, since 401(k) and IRA withdrawals are taxed as income, you might be taxed in a higher tax bracket during retirement.

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You’re Penalized for Early Withdrawals

Locking up your funds in an account that doesn’t let you withdraw until retirement without paying a penalty is an excellent way to ensure that your savings aren’t used for short-term purchases. However, what would you do in an emergency if you don’t have access to your savings?

Consider putting some of your savings into accounts that give you more flexibility for responding to unpredictable life events.

You’ll Probably Need More Money

There are contribution limits restricting how much you can save in a 401(k) or IRA. This year, the annual contribution limit for a 401(k) is $23,000, while the IRA limit is $7,000.

Depending on when you started putting money into these accounts, this may not be enough for you to retire without worrying about bringing in extra income. Look into other investment accounts, where you can build up your retirement savings even further.

You Need More Account Diversification

When it comes to investing of any kind, diversification is the key to reducing your risk. Each account also has different rules for when you can withdraw and when your savings are taxed.

Consider putting money into additional savings and investment accounts to gain more control over your income and taxes during retirement.

• Roth accounts: Roth 401(k) plans and IRAs offer tax-free withdrawals after you reach the age of 59 1/2. Since they’re funded by after-tax dollars and don’t have required minimum withdrawals, you have more flexibility when managing your taxes during retirement.

• Taxable brokerage accounts: If you don’t sell a stock for more than a year, then your investments are taxed at the lower long-term capital gains rate, lowering your overall tax bill.

• Health savings accounts (HSAs): Contributions to an HSA reduce your taxable income, and you can withdraw funds for qualified medical costs tax-free. Once you reach retirement age, HSA accounts no longer have to be set aside for medical bills — you can use the account for anything you want.

• Annuities: Both fixed and variable annuities provide guaranteed income streams during retirement, which can provide peace of mind. Growth is tax-deferred, but withdrawals are taxed as regular income. While they provide a reliable source of income, they typically have higher fees than other investment accounts.

• Taxable municipal bonds: Interest in these accounts is exempt from the federal income tax and sometimes state and local taxes.

What’s Wrong With Saving in a 401(k) or IRA for Retirement?

There’s nothing wrong with putting your savings into a 401(k) or traditional IRA for retirement — it shows that you’re thinking ahead. After all, only 57% of retirees have a tax-deferred retirement account, according to the Federal Reserve.

But don’t let these two accounts serve as your entire retirement planning strategy. Be aware of their limitations and find ways to spread out your contributions into other accounts that can help grow your investments.

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This article originally appeared on GOBankingRates.com: 4 Reasons You Need More Than Just Your 401(k) and IRA To Retire Comfortably