Commingled Accounts: Where “Yours, Mine, and Ours” Gets Complicated
Every California divorce runs into the same basic sorting exercise: figure out what belongs to the marriage and what belonged to one spouse alone before the marriage started. In theory, this is simple. Property acquired before marriage, or received individually as a gift or inheritance, stays separate. Everything else acquired during marriage is community property, split down the middle. In practice, years of shared bank accounts and joint mortgage payments, plus one spouse quietly depositing an inheritance into a checking account both people used, can turn that clean line into something closer to a Jackson Pollock painting.
The Default Assumption Favors the Community
California Family Code Section 760 establishes the baseline: property acquired by a married person during the marriage is presumed to be community property, regardless of whose name is on the account. That presumption is not a minor technicality. It means the spouse claiming that funds are actually separate property carries the burden of proving it, not the other way around. Silence, or a shrug and “well, everyone knows that account was mine,” does not satisfy a court.
Enter Tracing
When separate and community funds have been mixed in one account, the spouse claiming a separate interest has to trace the money back to its origin. California courts generally recognize two approaches. Direct tracing uses bank records to show a specific asset was purchased with identifiable separate funds, with intent to use separate rather than community money. Family expense tracing, or the recapitulation method, works backward through household finances to argue that community income was already exhausted on ordinary living expenses, so remaining separate funds must have paid for the disputed asset.
Both methods demand real documentation. Bank statements, closing documents, and old account records that a spouse might otherwise toss during a routine cleaning binge can become the entire case. If contributions cannot be traced and identified with reasonable specificity, courts will typically treat the whole commingled account as community property. Ambiguity does not split the difference. It defaults against the person who let the funds mix in the first place.
Reimbursement Is Not the Same as Ownership
Even when tracing succeeds for a particular contribution, that does not automatically restore full separate ownership of the resulting asset. A spouse who documents that separate funds went toward a down payment or paid down a loan principal on a jointly titled asset may instead be entitled to reimbursement for that contribution, while the underlying asset remains community property. Knowing which outcome applies can turn a short conversation with an attorney into thousands of dollars saved or lost at trial.
Protecting What Is Actually Yours
The best time to prevent a commingling dispute is well before anyone files for divorce: keeping an inheritance in a separate account, documenting a down payment’s source, and resisting the urge to “simplify” by merging everything into one joint account. The second best time is the moment a divorce becomes likely, while records can still be gathered before memories fade. Our San Francisco property division lawyers spend a significant part of their practice untangling exactly this kind of financial history, working alongside forensic accountants when the numbers demand it.
If you are heading into a divorce with assets that started out separate but have spent years mixed into shared accounts, do not assume the story is already written. Contact Cardwell Steigerwald Young LLP so we can start building the record that protects what is yours.
