§4.06 Commingled Funds

When separate property and community property are commingled in an account, tracing issues may arise. If the commingled funds are used to purchase property, the party who deposited the separate funds may attempt to trace the source of the funds used to purchase the property to establish that it is separate. Tracing may overcome the presumption that property acquired during marriage is community. [Marriage of Mix (1975) 14 C3d 604, 610–611.]

If you find that separate and community property or funds are commingled in such a manner that it is impossible to trace the source of the property or funds, the whole must be treated as community property. [Marriage of Mix, supra, 14 C3d at 610–611 n6.]

You can use either of two methods of tracing to establish that property purchased with commingled funds is separate property. See §§4.07–4.08 for these methods.