Opening a joint investment account with your spouse can be a sensible move: it pools your investing, gives each of you full access, and, titled correctly, lets the survivor take over without probate. The real decision isn’t whether to open one — it’s how to title it. The ownership structure you pick at the application screen determines how income lands on your tax return, what the surviving spouse pays in capital gains later, and whether one spouse’s creditor can reach the balance.
How to Title the Account
Brokerages present the titling choice as a dropdown, but the options behind it create meaningfully different rights during your lifetime and different outcomes at death.
Joint Tenancy With Right of Survivorship
JTWROS is the default most brokerages present to married couples. Each spouse owns an equal, undivided interest in the whole balance regardless of who deposited the money, and when one spouse dies, the survivor automatically becomes sole owner. A certified death certificate to the brokerage is enough. No probate, no executor, no waiting. If simplicity and immediate access for the survivor are what you want, JTWROS is the cleanest option.
Tenancy in Common
Tenancy in Common lets each spouse own a defined percentage, and those percentages don’t have to be equal. There is no automatic survivorship. When one spouse dies, that share becomes part of their estate and passes under their will or state intestacy rules, which usually means probate. Couples who want their share to go somewhere other than the surviving spouse (children from a prior marriage, for example) sometimes choose TIC for that reason, often holding the interest inside a revocable living trust to avoid probate while preserving the split.
Tenancy by the Entirety
Tenancy by the Entirety is available only to married couples, and only in the roughly 18 states plus the District of Columbia that recognize it for personal property like brokerage accounts. It works like JTWROS on death, with automatic transfer to the survivor, but it adds real creditor protection: the law treats the couple as a single owner, so a creditor with a judgment against only one spouse generally can’t seize the account. If your state allows TBE for investment accounts and asset protection is on your list, ask the brokerage whether they support this titling.
Community Property
If you live in Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, or Wisconsin, community property rules apply, and most assets acquired during the marriage are equally owned no matter how the account is titled or who funded it.1Internal Revenue Service. Publication 555 (12/2024), Community Property That treatment brings a significant tax benefit at death, described below.
How the Account Is Taxed Year to Year
A joint brokerage account is fully taxable. Every dividend, interest payment, and realized gain generates a tax bill in the year it happens.
What Ends Up on Your Return
The brokerage issues a consolidated Form 1099 at year-end covering dividends (1099-DIV), interest (1099-INT), and sale proceeds (1099-B). The form is tied to the primary account holder’s Social Security Number, but that SSN doesn’t decide who owes the tax.
If you file jointly, none of it matters procedurally: the whole 1099 goes on your shared 1040. Filing separately is where it gets fiddly. The spouse whose SSN is on the 1099 reports the full amount, then subtracts the other spouse’s share as a “Nominee Distribution,” and the other spouse reports their share on their own return. Unlike nominee arrangements with non-spouses, you don’t have to issue a separate 1099 to your spouse.2Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses For a JTWROS account the natural split is 50/50; for TIC it follows the ownership percentages. Deviating from those defaults requires clear documentation of who contributed what.
Gains and losses on sales go on Form 8949 and roll up to Schedule D.2Internal Revenue Service. Publication 550 (2025), Investment Income and Expenses The basis is generally what you originally paid.3Internal Revenue Service. Publication 551 (12/2025), Basis of Assets Joint ownership doesn’t change any of the underlying rules.
The Wash Sale Trap Across Spousal Accounts
The wash sale rule applies across your and your spouse’s accounts. If you sell a stock at a loss in the joint account and your spouse buys the same stock within 30 days in their IRA or a separate brokerage account, the loss is disallowed. It works the other direction too. Brokerages don’t track this across firms, so you have to watch it yourselves.
The 3.8% Surtax at Higher Incomes
The net investment income tax adds 3.8% on investment income once modified adjusted gross income passes $250,000 for married filing jointly.4Internal Revenue Service. Topic No. 559, Net Investment Income Tax The threshold is fixed by statute and doesn’t adjust for inflation, so more couples cross it each year. A large realized gain in the joint account can push you over on its own.
The Non-Citizen Spouse Boundary
Funding the account entirely with one spouse’s money is technically a gift to the other. For U.S. citizen spouses, the unlimited marital deduction means it doesn’t matter. The unlimited deduction does not apply when the receiving spouse is not a U.S. citizen.5Office of the Law Revision Counsel. 26 USC 2523 – Gift to Spouse A separate annual exclusion applies instead: $194,000 for 2026. Transfers above that in a single year require Form 709 and start using the donor’s lifetime exemption.6Internal Revenue Service. Instructions for Form 709 (2025) If one of you isn’t a U.S. citizen and the plan is to fund the account with a large lump sum, this needs planning.
What Happens When One Spouse Dies
Titling controls both the probate question and, less obviously, the future tax basis of the account.
A JTWROS account bypasses probate. The surviving spouse sends the brokerage a certified death certificate, the firm retitles the account into their name alone, and access continues within days. A TIC account doesn’t. The deceased spouse’s percentage share becomes part of their probate estate and passes under their will or intestacy, with the delay and legal fees that implies.
The Half Step-Up vs. Full Step-Up
This is the surprise that costs surviving spouses the most, and it usually shows up years later when they sell.
Inherited property generally gets a “stepped-up” basis equal to its fair market value on the date of death. Higher basis, less taxable gain when the survivor sells. In common law states, a JTWROS account gets only a half step-up: the deceased spouse’s 50% share resets to current market value, but the surviving spouse’s original 50% keeps its old purchase-price basis. In community property states, both halves reset.7Office of the Law Revision Counsel. 26 U.S. Code 1014 – Basis of Property Acquired From a Decedent
Concrete numbers make the difference clear. A couple bought $200,000 of stock that grew to $1,000,000. In a common law JTWROS account, the half step-up leaves $400,000 of embedded gain in the survivor’s share. In a community property state, the full step-up eliminates all $800,000 of unrealized gain. On a portfolio that size, the tax savings can easily exceed $100,000.
Planning for the Second Death
JTWROS handles the first death well, but not the second. A Transfer on Death registration lets you name primary and contingent beneficiaries who inherit whatever’s left when the surviving spouse dies, avoiding probate a second time. Most major brokerages support TOD on joint accounts. Without one, the account becomes part of the surviving spouse’s estate.
Creditor Exposure
Marriage doesn’t shield a joint brokerage account from a creditor of one spouse. How much protection you actually have depends on state law and titling.
In common law states with a standard JTWROS account, a creditor holding a judgment against only one spouse can often garnish that spouse’s interest in the joint account. Some states allow the creditor to reach up to half the balance. Others restrict garnishment to debts that benefited both spouses or the family. Rules vary widely.
In community property states, exposure is broader. Spouses share liability for debts incurred during the marriage, so a judgment creditor of one spouse can typically garnish the joint account regardless of which spouse incurred the debt. In some community property states, a creditor can even reach a spouse’s separate account to satisfy the other spouse’s obligation.
Tenancy by the Entirety, where available, is the strongest protection. Because neither spouse individually owns a separable share, a creditor with a judgment against only one spouse generally can’t touch the account at all. Only a creditor holding a judgment against both spouses jointly can garnish TBE assets.
Regardless of titling, funds traceable to protected sources like Social Security, disability payments, or veterans’ benefits may be exempt from garnishment under federal law.
What Happens in a Divorce
The account is marital property subject to division. Most states follow equitable division, which doesn’t necessarily mean 50/50; courts weigh contributions, length of marriage, earning capacity, and other state-specific factors. Community property states start from a presumption of equal division but can deviate.
The account is either liquidated with proceeds divided, or the brokerage splits it into two individual accounts. If it holds appreciated securities, watch which spouse gets which lots. Basis travels with the shares, so a spouse who receives low-basis stock inherits a larger future tax bill than the one who gets high-basis stock or cash, even when the current market values are identical.
Opening and Running the Account
You’ll both need government-issued identification and Social Security Numbers. During the application, the brokerage will ask you to pick the ownership structure. That’s the conversation to have before you click through: JTWROS, TIC, or TBE if your state allows it. Retitling later is possible but can trigger its own tax and legal complications.
Funding
ACH transfer from a linked bank account is the standard method, free at most brokerages but subject to daily limits, often between $25,000 and $100,000. Larger deposits usually go by wire for same-day availability, with a fee from the sending bank. If you’re moving existing holdings from another firm, an Automated Customer Account Transfer Service (ACATS) transfer moves the securities directly without selling, preserving each position’s cost basis and holding period.8DTCC. Automated Customer Account Transfer Service (ACATS) Most ACATS transfers finish in about a week.9FINRA. Customer Account Transfers
SIPC Coverage
If the brokerage fails, SIPC protects customer assets up to $500,000 per account capacity, including a $250,000 cash limit. A joint account is a separate capacity from either spouse’s individual accounts at the same firm.10SIPC. Investors with Multiple Accounts A couple can have $500,000 of coverage on the joint account plus another $500,000 on each spouse’s individual account at the same brokerage. SIPC covers broker insolvency, not market losses.
Access and the POA Boundary
Both spouses get full, independent authority. Either of you can trade, deposit, or withdraw without the other’s approval, whether the account is JTWROS or TIC. That flexibility is the point, but there’s no built-in safeguard if trust breaks down or one spouse trades recklessly. Some couples set alerts so both receive notifications on every transaction.
One thing joint titling doesn’t replace: a durable power of attorney. Joint access helps if one spouse is temporarily unavailable, but a joint account holder has no fiduciary duty to the other. A POA does, and it’s the proper tool for incapacity planning on accounts outside the joint structure.