Date of separation
Dissolution and legal separationIn community property and equitable distribution states alike, the separation date is the line that divides what the marriage accumulated from what each spouse accumulated alone. In Washington, earnings and accumulations while living separate and apart are separate property (RCW 26.16.140).
What the record must show: Account balances on the separation date, plus the transaction history on either side of it to trace transfers, withdrawals, and post-separation deposits.