What to Do When You Inherit a Brokerage Account and the Cost Basis Steps Up (September 2026)

When you inherit a brokerage account, the cost basis steps up to the asset’s fair market value on the date of the original owner’s death. Our team walks through what this means, what you should do next, and how to avoid common tax mistakes during estate settlement.

If a parent, spouse, or other loved one has passed and left you a taxable brokerage account, the term “step-up in basis” will matter more than almost anything else in the next few months. It is the single biggest tax advantage available to beneficiaries of appreciated assets, and getting it right requires both paperwork and timing.

This guide covers the basics of how the step-up works, the differences between community property and common law states, what executors must do, and a practical checklist for beneficiaries in 2026.

What Is a Step-Up in Basis and How Does It Work?

A step-up in basis is a tax rule that resets an inherited asset’s cost basis to its fair market value on the date of the original owner’s death. Instead of inheriting the original purchase price, you inherit the value the asset had at the moment of death, which can eliminate capital gains tax on decades of appreciation.

The IRS Definition

Under Internal Revenue Code Section 1014, property acquired from a decedent receives a new basis equal to the fair market value on the date of death (or the alternate valuation date if the executor elects). The “step-up” terminology refers to the difference between the original purchase price and the new stepped-up value.

If your father bought 500 shares of a stock for $10 each in 1995 ($5,000 total) and those shares were worth $80 each ($40,000) when he died, your cost basis becomes $40,000. Sell immediately at that price and you owe zero capital gains tax on the $35,000 of appreciation.

Date of Death Valuation

The valuation date is typically the day the original owner died, although the executor may elect an alternate valuation date six months after death for estate tax purposes. Most modern brokerages handle this valuation automatically using the closing price on the date of death for publicly traded securities.

For mutual funds, the date-of-death NAV (net asset value) is used. For illiquid assets such as private stock or real estate, a qualified appraisal may be required.

How the Cost Basis Changes When You Inherit a Brokerage Account?

When you inherit a brokerage account, every holding inside that account receives its own stepped-up basis at the fair market value on the date of death. The account structure itself is retitled in your name, but each security keeps its individual adjusted basis.

Original Cost Basis vs. Stepped-Up Basis

The original cost basis is the price the deceased paid, plus reinvested dividends, commissions, and any capital return adjustments. The stepped-up basis replaces that figure entirely with the date-of-death value. Going forward, your gain or loss is measured from this new starting point.

This is fundamentally different from gifting during life. If the original owner had given you the stock before death, your basis would carry over from the donor. Gifting forfeits the step-up, which is why most planners recommend holding appreciated assets until death when possible.

What Assets Qualify

Most assets held in a taxable brokerage account qualify for the step-up. This includes individual stocks, ETFs, mutual funds, bonds, money market funds, and most exchange-traded products. It also applies to real estate, private business interests, and many other capital assets held outside retirement accounts.

Assets that do NOT get a step-up include retirement accounts such as traditional IRAs and 401(k)s, which pass through under different rules and remain fully taxable to the beneficiary. Foreign assets held through certain entities may also have special rules.

Tax Implications for Beneficiaries After the Step-Up

The tax implications of inheriting a brokerage account are mostly favorable at the moment of transfer. You inherit no income tax liability for appreciation that occurred during the decedent’s lifetime, and there is no federal estate tax concern unless the estate exceeds the federal exemption (currently $13.61 million in 2026).

Capital Gains Tax Reset

Once the basis is stepped up, only post-inheritance appreciation creates taxable gain. If you sell immediately at roughly the date-of-death value, your capital gains tax liability is essentially zero. If you hold for years and the position grows, only the post-inheritance growth is taxed when you eventually sell.

This is why many beneficiaries sell inherited positions shortly after receiving them, especially if the position is concentrated, volatile, or no longer matches their investment plan. The “step-up plus immediate sale” strategy is a clean way to reset exposure without creating a tax bill.

Holding Period Considerations

Inherited assets automatically receive long-term capital gains treatment regardless of how long the beneficiary actually holds them. This is one of the few places in the tax code where a one-day holding period qualifies for the lower long-term rate. Any sale after inheritance qualifies for long-term treatment under IRC Section 1223(9).

Step-by-Step Process After Inheriting a Brokerage Account

Here is the sequence our team recommends once you are notified that you are a beneficiary of a brokerage account.

Step 1: Locate the Account

Ask the executor or estate attorney for a complete list of accounts. Look for statements, old tax returns, online login records, and any correspondence with brokerages. If you cannot locate an account, search the SEC’s Investment Adviser Public Disclosure database and the National Association of Insurance Commissioners life insurance database, since unclaimed property is often reported to state treasuries.

Step 2: Gather Documents

You will need a certified death certificate, the will or trust document naming you as beneficiary, and your own identification. If the estate goes through probate, you will also need letters testamentary appointing the executor. For non-probate transfers, a small estate affidavit or beneficiary claim form may suffice.

Step 3: Notify the Broker

Contact each brokerage by phone or through their beneficiary claims portal. Most firms have dedicated inheritance teams. Submit the death certificate, your ID, and any required forms (often a Transfer on Death or POD/Beneficiary claim form). The firm will retitle the account in your name or open a new inherited account.

Step 4: Confirm the Stepped-Up Basis

Once the account transfers, verify that the brokerage has recorded the date-of-death fair market value for each holding. This information typically appears in the cost basis section of your statements. If a position shows the wrong basis, request a correction in writing and keep records.

Step 5: Decide Whether to Hold or Sell

Talk with a tax advisor before selling. While the step-up eliminates gain to date of death, post-inheritance gains are taxable, and concentrated positions carry their own risks. Some beneficiaries sell immediately to diversify; others hold for years because of low basis or sentimental value.

Community Property vs. Common Law States

State law matters because it affects how much of a jointly owned account gets stepped up. About a dozen states follow community property rules, while the rest follow common law.

Why State Law Matters

In community property states, half of the community property automatically belongs to the surviving spouse. Upon the death of the first spouse, BOTH halves of the community property get a step-up in basis. In common law states, only the deceased’s portion is stepped up, and the surviving spouse’s share retains the original basis.

Community property states include Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin. Alaska, South Dakota, Tennessee, and Kentucky allow opt-in community property trusts.

A Side-by-Side Comparison

Common Law States: The deceased’s share receives a step-up. The surviving owner’s share retains the original cost basis. Only one step-up occurs per asset in most cases.

Community Property States: 100 percent of community property receives a step-up at the first spouse’s death. A second step-up may occur when the surviving spouse dies. This produces a “double step-up” for assets held until both spouses pass.

The double step-up is one reason high-net-worth couples in community property states often leave assets to the surviving spouse rather than directly to children.

Joint Accounts, Trusts, and Special Situations

Not all inherited brokerage accounts follow the standard rules. Joint accounts and trust-owned assets have nuances worth understanding.

Joint Brokerage Accounts

For a non-spouse joint account, the step-up only applies to the deceased’s portion, and the surviving owner’s basis for the deceased’s share becomes the date-of-death value. If your brother added you as a joint owner on his account and passed away, only his half gets the step-up; your original contribution retains its original basis.

For spouses with joint accounts, the rules differ depending on state law. In common law states, the surviving spouse is treated as having received half the account by right of survivorship, with the other half potentially subject to inclusion in the estate depending on contribution history.

Trust-Owned Assets

Assets held inside a revocable living trust generally receive a step-up because the trust is treated as part of the decedent’s estate for income tax purposes. Assets held in an irrevocable trust, however, generally do NOT receive a step-up because they are not considered owned by the decedent at death. This is a critical distinction for families using trusts for estate planning.

Common Mistakes to Avoid With Stepped-Up Basis

Our team has seen beneficiaries and executors make the same handful of mistakes year after year. Avoid these pitfalls during estate settlement.

Mistakes Beneficiaries Make

Selling before confirming the stepped-up basis. Some beneficiaries rush to liquidate and accidentally report the original cost basis, creating a phantom tax bill.

Forgetting to update state tax records. The federal step-up also applies to state income tax in most states, but not all. Verify your state’s treatment.

Ignoring concentrated positions. A single inherited stock can dominate a portfolio. Even with no tax cost, the risk may warrant diversification.

Mistakes Executors Make

Failing to record date-of-death values. Without documentation, beneficiaries have no proof of basis if the brokerage record is wrong years later.

Distributing assets before retitling. Once distributed, the basis correction becomes harder. Keep assets in the estate account until documentation is complete.

Missing the alternate valuation election. If estate assets decline within six months of death, the executor may elect an alternate valuation date to reduce both estate tax and stepped-up basis.

Action Checklist for Beneficiaries

Use this checklist as soon as you are notified of an inheritance:

• Request multiple certified copies of the death certificate

• Locate all brokerage statements, old tax returns, and account numbers

• Identify the executor and request documentation

• Contact each brokerage’s beneficiary claims team

• Submit the death certificate, your ID, and beneficiary forms

• Confirm the stepped-up basis is reflected in your account

• Decide whether to hold, sell, or reposition inherited holdings

• Consult a CPA or tax advisor before year-end

• Retain all basis documentation permanently

FAQs

Final Thoughts on Inheriting a Brokerage Account

Inheriting a brokerage account with a stepped-up basis is one of the most powerful tax benefits in the U.S. system, but the paperwork and timing matter. Confirm the new basis, document everything, and talk with a tax professional before making major sales decisions in 2026.

What to do when you inherit a brokerage account and the cost basis steps up boils down to three things: gather the right documents, confirm the brokerage recorded the date-of-death value, and decide intentionally whether to hold or sell. With those steps handled, the step-up does most of the heavy lifting on its own.