Joint Account

The choice among JTWROS, TIC, and community-property titles is a planning decision, not an operational one. JTWROS keeps assets out of probate and gives the survivor immediate access — convenient for spouses, but it overrides the will entirely for that account. TIC gives each owner a discrete (often equal) percentage that flows through the deceased's estate plan, useful when owners want different ultimate beneficiaries (siblings, business partners). Community-property titling applies in CA, AZ, ID, LA, NM, NV, TX, WA, and WI; the form unlocks the double step-up in basis at the first spouse's death — a meaningful tax break that most non-CP-state spouses miss without proactively converting to community property.

Functionally, joint accounts share signing authority among owners (any owner can transact unless the account is restricted). All owners' Social Security numbers must be on file, but only one is the 'primary' for IRS reporting unless the account is structured otherwise. Cost-basis tracking is split or unified depending on the custodian — some custodians track each owner's basis contribution separately for non-spouse joint accounts; most consolidate when the joint owners are spouses.

For non-spouse joint accounts (parent-child, siblings, unmarried partners), the tax mechanics are messier than commonly understood. Adding a non-spouse to a JTWROS account is technically a gift (subject to gift-tax reporting if it crosses the annual exclusion), and the survivor's basis step-up is partial — only the deceased's contribution percentage steps up, while the survivor retains their original basis on their portion.