What Is Required to Open a Joint Brokerage Account?

Updated July 9, 2026 5 min read

Two people deciding to invest together, whether partners, spouses, or family members, often reach for a joint brokerage account without realizing how many small decisions the application actually asks them to make upfront.

The short answer

Opening a joint brokerage account generally requires both individuals to provide identifying and financial information, agree to the account terms, and choose a legal registration type that determines how the account is owned and what happens to it if one owner dies. Both people are typically treated as equal account holders with independent authority to transact.

The paperwork side

A joint brokerage account application generally asks each owner for identifying details such as Social Security number, address, employment information, and often some background on investing experience and financial situation, since brokerages use this to assess suitability for certain products. Both parties typically need to sign or otherwise consent electronically, and most firms require this regardless of whether the two owners are married, related, or simply investing together.

Choosing a registration type

The registration choice matters because it directly determines what happens to the assets later, and it’s generally difficult to change without closing and reopening the account, so it’s worth discussing before submitting the application rather than defaulting to whatever the form suggests first.

What both owners can typically do

Once open, either owner on a joint account can usually place trades, withdraw funds, or make changes without needing the other’s sign-off for each transaction, which is a meaningful difference from a custodial investment account for a child where one adult holds sole authority. This shared access is convenient for coordinated investing but also means both owners are trusting each other with full control over jointly held assets. It’s a different arrangement entirely from opening a brokerage account as a single individual owner, where there’s never a question of shared authority to begin with.

What to weigh before applying

The bottom line

Opening a joint brokerage account is mostly a matter of paperwork, but the registration type chosen at setup has lasting consequences for ownership and inheritance. Taking the time to understand the difference between JTWROS and tenants in common before signing tends to prevent confusion much later.