Tax Implications of Inherited Investment Accounts

Receiving an inheritance is rarely simple — and when investment accounts are involved, the tax consequences can be significant, immediate, and easy to get wrong.

The rules differ dramatically depending on what type of account you inherit. A taxable brokerage account, a traditional IRA, a Roth IRA, and a 401(k) each follow their own set of rules. Making the wrong move — like cashing out an inherited IRA without understanding the distribution requirements — can trigger a tax bill that wipes out a meaningful portion of what you received.

This guide walks through each major account type, explains how the tax rules work, and identifies the planning opportunities that beneficiaries most commonly miss.

When someone passes away, the tax treatment of their investment accounts does not automatically transfer to the beneficiary. Instead, each account type carries its own set of rules that govern:

• Whether a stepped-up cost basis applies (which can eliminate capital gains on appreciated assets)
• Whether distributions are taxable (and at what rate)
• How quickly you must withdraw the funds (distribution timelines vary widely)
• Whether you can stretch distributions over your lifetime or must empty the account within 10 years

Understanding these distinctions before you take any action is critical. Distributions from inherited accounts are generally irreversible, and mistakes cannot be undone.

A taxable brokerage account — one that holds stocks, bonds, mutual funds, or ETFs outside of any retirement account wrapper — is typically the most tax-favorable type of account to inherit.

When you inherit a taxable investment account, the cost basis of every asset in that account is "stepped up" to the fair market value on the date of the decedent's death (or, in some cases, an alternate valuation date six months later if the estate elects it).

This means that decades of unrealized capital gains are effectively erased.

Example: Your parent purchased 1,000 shares of a stock in 1995 for $10 per share ($10,000 total). At the time of their death, those shares are worth $150 per share ($150,000 total). If you inherit those shares, your cost basis is $150,000 — not $10,000. If you sell immediately, you owe zero capital gains tax on $140,000 of appreciation that built up over 30 years.

This is one of the most powerful wealth-transfer mechanisms in the tax code, and it is entirely legal.

Once the basis is stepped up, you hold the assets as your own. Any future appreciation from the date of death forward will be subject to capital gains tax when you eventually sell — at either short-term or long-term rates depending on how long you hold the assets after inheriting them.

Assets held for more than one year after the date of death qualify for long-term capital gains rates (0%, 15%, or 20% depending on your income). Assets sold within one year of the date of death are taxed at short-term rates (ordinary income rates).

If the decedent lived in a community property state (Arizona, California, Texas, Nevada, Washington, Idaho, Louisiana, New Mexico, or Wisconsin), the surviving spouse may receive a full stepped-up basis on the entire community property — not just the decedent's half. This is a significant planning opportunity for married couples.

A traditional IRA is funded with pre-tax dollars. The original owner received a tax deduction when contributions were made, and the account grew tax-deferred. When distributions are taken — whether by the original owner or a beneficiary — they are taxed as ordinary income.

There is no stepped-up basis for inherited IRAs. Every dollar you withdraw is taxable.

The SECURE Act of 2019 fundamentally changed inherited IRA rules for most beneficiaries. Prior to the SECURE Act, non-spouse beneficiaries could "stretch" distributions over their own life expectancy — sometimes over decades. That strategy is largely gone.

Under current law, most non-spouse beneficiaries must fully empty an inherited traditional IRA within 10 years of the original owner's death. There are no required minimum distributions (RMDs) in years 1 through 9 — you can take nothing, or take everything, or anything in between — but the account must be fully distributed by December 31 of the 10th year.

The IRS clarified in 2024 that if the original owner had already begun taking RMDs, beneficiaries subject to the 10-year rule must also take annual RMDs in years 1 through 9 (based on the beneficiary's life expectancy), with the remaining balance distributed in year 10. This rule caught many beneficiaries off guard and resulted in significant penalties for those who missed distributions in 2021–2023 (the IRS waived penalties for those years, but the waiver period has ended).

Certain beneficiaries are exempt from the 10-year rule and can still stretch distributions over their life expectancy. These "eligible designated beneficiaries" include:

• Surviving spouses (who have additional options, including treating the IRA as their own)
• Minor children of the original owner (until they reach the age of majority, at which point the 10-year rule kicks in)
• Disabled individuals (as defined under IRC Section 72(m)(7))
• Chronically ill individuals
• Beneficiaries who are not more than 10 years younger than the original owner

If you fall into one of these categories, the planning landscape is significantly more favorable.

A surviving spouse has the most flexibility of any beneficiary. They can:

1. Roll the inherited IRA into their own IRA — treating it as if it were always theirs, with their own RMD schedule beginning at age 73
2. Keep it as an inherited IRA — which allows distributions before age 59½ without the 10% early withdrawal penalty (useful if the surviving spouse is younger and needs income)

The right choice depends on the surviving spouse's age, income needs, and overall tax situation.

Because the 10-year rule gives you flexibility on when to take distributions (not just that you must), there is real planning opportunity here. Taking large distributions in years when your income is lower — perhaps before Social Security begins, or before a business sale, or during a year with significant deductions — can reduce the overall tax cost significantly.

Spreading distributions evenly over 10 years is often not the optimal strategy. A tax projection for each year of the distribution window is worth the investment.

An inherited Roth IRA is treated very differently from a traditional IRA in one critical respect: qualified distributions are tax-free.

Because the original owner contributed after-tax dollars, the growth inside a Roth IRA is never subject to income tax — as long as the account has been open for at least five years (the "five-year rule").

If you inherit a Roth IRA that was opened less than five years before the original owner's death, distributions of earnings (not contributions) may be taxable until the five-year period is satisfied. The five-year clock starts on January 1 of the year the original owner made their first Roth IRA contribution — not the year they died.

In most cases, inherited Roth IRAs have already satisfied the five-year rule, making all distributions fully tax-free.

Non-spouse beneficiaries are still subject to the 10-year rule for inherited Roth IRAs — the account must be fully distributed within 10 years of the original owner's death. The key difference is that those distributions are tax-free.

This creates a planning opportunity: because there is no tax cost to waiting, beneficiaries can let the Roth IRA continue growing tax-free for the full 10 years before taking the final distribution. The longer the funds remain in the account, the more tax-free growth accumulates.

A surviving spouse can roll an inherited Roth IRA into their own Roth IRA, eliminating the 10-year rule entirely and allowing the account to continue growing tax-free indefinitely (Roth IRAs have no RMDs for the original owner during their lifetime).

Inherited 401(k) and 403(b) accounts follow rules similar to inherited traditional IRAs — distributions are taxable as ordinary income, and the 10-year rule applies to most non-spouse beneficiaries.

However, there are some important differences:

Non-spouse beneficiaries cannot roll an inherited 401(k) directly into their own IRA. They can, however, roll it into an inherited IRA (also called a beneficiary IRA). This is almost always advisable because:

• Inherited IRAs typically offer more investment options than employer plans
• The 10-year distribution rules are the same, but the inherited IRA gives you more control over timing
• Some employer plans require lump-sum distributions to non-spouse beneficiaries, which would trigger a massive one-year tax bill

The rollover to an inherited IRA must be done as a direct trustee-to-trustee transfer. If the funds are paid to you directly, 20% mandatory withholding applies, and you have 60 days to complete the rollover — a tight window that creates unnecessary risk.

A surviving spouse has the same flexibility as with an inherited IRA: they can roll the 401(k) into their own IRA (or their own 401(k) if their employer plan allows it), or keep it as an inherited account. Rolling into their own IRA is usually the better long-term choice.

If the decedent had a Roth 401(k), the same tax-free distribution rules apply — but unlike a Roth IRA, Roth 401(k)s were subject to RMDs during the original owner's lifetime (for plan years before 2024). The SECURE 2.0 Act eliminated Roth 401(k) RMDs starting in 2024. For inherited Roth 401(k)s, rolling to an inherited Roth IRA is typically the cleanest approach.

Annuities held outside of retirement accounts (non-qualified annuities) do not receive a stepped-up basis. The growth inside a non-qualified annuity is taxed as ordinary income when distributed — not at capital gains rates.

Beneficiaries of non-qualified annuities generally have several distribution options:

• Lump sum — fully taxable in the year received
• Five-year rule — distribute the full balance within five years
• Annuitize over life expectancy — spread distributions (and the tax) over time

The "exclusion ratio" determines what portion of each payment is a tax-free return of the original premium versus taxable gain. An inherited annuity with significant growth can create a substantial ordinary income tax liability, and the timing of distributions matters considerably.

For larger estates, the federal estate tax may apply before any of the above rules come into play. In 2026, the federal estate tax exemption is $13.99 million per individual ($27.98 million for married couples with proper planning). Estates below these thresholds owe no federal estate tax.

However, the current exemption amounts are scheduled to sunset at the end of 2025 under the Tax Cuts and Jobs Act — unless Congress acts to extend them. If the sunset occurs, the exemption reverts to approximately $7 million (inflation-adjusted), which would bring significantly more estates into the taxable range.

Some states also impose their own estate or inheritance taxes with lower exemption thresholds. Arizona does not have a state estate or inheritance tax, but beneficiaries in other states should verify their state's rules.

1. Taking a lump-sum distribution from an inherited IRA without planning This is the most expensive mistake. A large lump-sum distribution can push you into the highest federal income tax bracket, trigger the Net Investment Income Tax (3.8%), and phase out deductions and credits. Spreading distributions over the 10-year window almost always produces a better outcome.

2. Missing the 60-day rollover window If an inherited 401(k) is paid directly to you rather than transferred trustee-to-trustee, you have 60 days to roll it into an inherited IRA. Missing this window means the entire distribution is taxable — and there is no do-over.

3. Failing to take required distributions from an inherited IRA If the original owner had already begun RMDs, beneficiaries subject to the 10-year rule must also take annual distributions in years 1–9. Missing these distributions triggers a 25% excise tax (reduced to 10% if corrected promptly).

4. Selling inherited brokerage assets before confirming the stepped-up basis The custodian's records may not automatically reflect the correct stepped-up basis. Before selling any inherited securities, confirm that the basis has been updated to the date-of-death value. Selling with the wrong basis means overpaying capital gains tax.

5. Treating all inherited accounts the same Each account type has different rules. A strategy that makes sense for an inherited brokerage account may be completely wrong for an inherited IRA.

1. Do not take any distributions immediately. You typically have time to plan. Rushing into a lump-sum withdrawal is almost never the right move.

2. Identify every account type. Get a complete picture of what you've inherited — taxable accounts, traditional IRAs, Roth IRAs, 401(k)s, annuities — before making any decisions.

3. Confirm your beneficiary classification. Are you a surviving spouse? An eligible designated beneficiary? A non-spouse beneficiary subject to the 10-year rule? Your classification determines your options.

4. Request a date-of-death valuation for all assets. This establishes the stepped-up basis for taxable accounts and documents the fair market value for estate purposes.

5. Model the tax impact of different distribution strategies. For inherited IRAs and 401(k)s, run projections across the 10-year window to identify the lowest-tax distribution schedule given your expected income each year.

6. Work with a tax professional before making any moves. The rules are complex, the stakes are high, and mistakes are difficult or impossible to reverse.

At Autarky Tax and Accounting, we work with beneficiaries to develop distribution strategies that minimize the tax cost of inherited accounts — whether that means modeling the optimal 10-year IRA distribution schedule, coordinating the stepped-up basis documentation for an inherited brokerage account, or advising on the rollover of an inherited 401(k).

Our team includes former IRS and US Treasury professionals who understand both the technical rules and how the IRS evaluates compliance in this area. If you've recently inherited investment accounts — or are planning your own estate to minimize the tax burden on your heirs — we'd welcome the conversation.

Schedule a free consultation to discuss your situation.