In California, dealing with your retirement plans in divorce can be extremely challenging and should require the help of an experienced family law attorney. In short, any asset or liability that was acquired during your marriage is considered community property, and you must split it with your spouse upon your divorce. You must divide everything, from your bank accounts to your time-shares and even your frequent flier miles. In that regard, retirement accounts are also subject to division, many times even if the plan was started prior to your marriage.
Generally, contributions you each make to your pension before the marriage or domestic partnership are separate property. Contributions made after the date of marriage or registration of the domestic partnership are community property, so they will be equally divided between parties in the divorce case.
Dividing your retirement plans in divorce is more complicated than dividing some other kinds of property. This is one of the situations where a lawyer’s help is necessary because how error prone the splitting of retirement plans can be. People don’t differentiate, or even understand, what kind of retirement plan they’re dealing with. There are defined-contribution plans—a 401(k) is the best example—and defined-benefit plans, which people usually think of as a pension. Each has its own issues and traps.