Pretax money is invested before any taxes have been deducted, while after-tax money is invested after taxes have been deducted. Investments in tax-deferred retirement accounts such as IRAs and 401(k)s are made pretax, which means there is a larger sum of money to invest. While applying taxes reduces the amount of money available to invest, sometimes after-tax investment vehicles such as Roth IRAs can produce better overall returns because, unlike pretax accounts, withdrawals from these after-tax accounts can be made without owing taxes. A financial advisor can help you evaluate after-tax and pretax investment options.

Pretax vs. After-Tax Basics

The terms “pretax” and “after-tax” when applied to income, expenses or contributions tell you whether taxes have been applied to the amount. Wages, for example, are normally after-tax, because the employer withholds taxes before handing out paychecks. Contributions to Roth-type retirement accounts and regular brokerage and bank accounts are also made after tax.

Many people save for retirement pretax by contributing money to IRAs and similar tax-advantaged accounts. These funds can be placed in a retirement account before any income taxes are levied. When you are preparing your tax return, any money you put into an IRA, for instance, is deducted from your total taxable earnings, which generally reduces your total tax liability.

Comparing Pretax and After-Tax

Investing money before taxes have been levied means you’ll be investing more than you would if you did it after paying taxes. And, all else equal, investing a larger sum means earning more from your investment. This simple rule of thumb underlies much of the popularity of saving for retirement pretax using IRAs and similar tax-advantaged accounts. If people could only save after-tax dollars in ordinary bank or brokerage accounts, there would be less incentive to sock away money in these accounts.

However, pretax is not always the best. Sums invested pretax in IRAs and similar retirement don’t completely evade taxation. Taxes on contributions as well as any earnings from investments in the account are only deferred. Savers will owe taxes later, at their then-current rate of taxation, when they withdraw funds from the account.

If the individual’s tax rate is lower in retirement, pretax investing can be advantageous. However, if you earn a lot of income over your career and have a large retirement nest egg, your required minimum distributions and other sources of income could mean your income and tax bracket are higher after you’ve retired than when you put money away pretax.

If an individual’s tax rate will be higher in retirement than it is at the time the investment was made, it can be better to invest after-tax in a Roth-type retirement account. This can work well for younger people just starting their careers before their earnings increase enough to put them in higher income-tax brackets. After paying taxes a relatively low rate when contributing, funds in these accounts grow tax-free and can be withdrawn later without owing any taxes.

Choosing Pretax or After-Tax

Deciding whether to invest pretax or after-tax requires considering your individual situation. Examine the following factors:

1. Account for investment returns: Start by looking at the expected rate of return on your investments.
2. Understand how taxes are applied: Capital gains on stocks held more than a year generally are taxed at a lower rate than ordinary income such as interest on bonds. Considering tax treatment of different types of income can help you decide on an after-tax or pretax investment.
3. Calculate returns after all taxes are applied: Roth IRA or Roth 401(k) withdrawals won’t incur taxes as long as the investor is age 59.5 or older and has had the account for at least five years. For pretax investments, it’s necessary to apply taxes to any sums withdrawn from the accounts before you can estimate the actual return. For instance, if you withdraw $10,000 from a pretax investment and are in a 25% tax rate in retirement, the amount left after taxes would be 75% of $10,000 or $7,500. Money invested in a regular brokerage account with no tax advantages has to pay any taxes due on the money before it’s invested as well as on earnings but as they are earned. However, withdrawing money from a regular account doesn’t usually trigger any additional taxes.
4. Compare post-tax and after-tax: For example, if you want to invest $10,000 in an after-tax account and you are in a 25% tax bracket, you’ll have to earn approximately $13,333 and pay $3,333 in taxes in order to have $10,000 available to invest. If that $10,000 earns 5% annually for 10 years, it will be worth $16,289. You can withdraw all of it without owing taxes after age 59.5 if the account is at least five years old.

Say instead you invest $13,333 in a pretax account, also 5%. After 10 years, you’ll have $21,718. If you withdraw the full amount and your rate is still 25%, you’ll owe $5,429 in taxes and be left with the same $16,289 as you got with the after-tax investment.

If, however, during the interim you have retired and your tax rate has dropped to 15%, you’ll only owe about $3,258 on emptying the pretax account. This will leave about $18,641. In this case, the pretax investment produces a larger return net of taxes.

If you are in the 15% bracket when you fund an after-tax investment and are in the 25% percent bracket when you retire, the situation is reversed. In that case, you’d need about $11,765 to have $10,000 to invest after tax. Again, you’d wind up with $16,289, which you can withdraw tax-free.

Investing $11,765 pretax at 5% gives you $19,164 after 10 years. a sizable increase. If you withdraw that amount when you are in the 25% bracket, however, your nominal tax liability will be $4,791, leaving you just $14,373. In this case, the after-tax investment generates a better overall result by about $1,916, which is the difference between $14,373 from the pretax method and $16,289 using an after-tax approach.

The Bottom Line

You can invest pretax before taxes are levied or after-tax after taxes have been applied. Pretax investing and after-tax investing both have advantages and drawbacks. Whether it is advisable to invest pretax or after-tax depends on individual circumstances, including whether you expect to be in a higher or lower tax bracket when you withdraw funds.

Investment Tips

• Deciding whether to invest pretax or after-tax requires you to understand your tax situation and financial goals. A financial advisor is well-equipped to help you do just that. Finding a financial advisor doesn’t have to be hard. SmartAsset’s free tool matches you with up to three vetted financial advisors who serve your area, and you can have a free introductory call with your advisor matches to decide which one you feel is right for you. If you’re ready to find an advisor who can help you achieve your financial goals, get started now.
• SmartAsset’s Investment & Return Calculator can make it much simpler to compare the relative advantages of after-tax and pretax investing.

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Mark Henricks
Mark Henricks has reported on personal finance, investing, retirement, entrepreneurship and other topics for more than 30 years. His freelance byline has appeared on CNBC.com and in The Wall Street Journal, The New York Times, The Washington Post, Kiplinger’s Personal Finance and other leading publications. Mark has written books including, “Not Just A Living: The Complete Guide to Creating a Business That Gives You A Life.” His favorite reporting is the kind that helps ordinary people increase their personal wealth and life satisfaction. A graduate of the University of Texas journalism program, he lives in Austin, Texas. In his spare time he enjoys reading, volunteering, performing in an acoustic music duo, whitewater kayaking, wilderness backpacking and competing in triathlons.