The California state legislature recently enacted a law that may affect the taxation of benefits an employer provides to same-sex domestic partners in the state. California AB 362 excludes from gross income for California state income tax purposes the amount of any tax gross-ups paid by an employer to an employee for benefits for that employee’s same-sex spouse or domestic partner. The law was approved by California’s governor on October 1, 2013, and is effective immediately through January 1, 2019.

Earlier this year the Supreme Court of the United States ruled in U.S. v. Windsor that Section 3 of the Defense of Marriage Act (DOMA) is unconstitutional (see “Supreme Court Rules on DOMA and California’s Proposition 8” for more). Section 3 of DOMA had provided that, for purposes of all federal laws, the word “marriage” means “only a legal union between one man and one woman as husband and wife,” and the word “spouse” refers “only to a person of the opposite-sex who is a husband or wife.” Subsequent Internal Revenue Service (IRS) and U.S. Department of Labor guidance clarified that, as a result of Windsor, favorable federal tax treatment of spousal benefit coverage would extend to all same-sex couples legally married in any jurisdiction with laws authorizing same-sex marriage, regardless of whether the couple currently resides in a state where same-sex marriage is recognized (see “IRS and DOL Guidance Clarifies Employee Benefits Impact of Supreme Court’s DOMA Ruling” for more information).

As a result of Windsor and the subsequent IRS guidance, the impact of California AB 362 appears fairly limited. Pre-Windsor, some employers provided a federal tax gross-up on the imputed value of coverage provided to an employee’s same-sex spouse or domestic partner. Post-Windsor, same-sex married couples in California no longer need a tax gross-up for either state or federal tax purposes because they no longer have to be taxed on the value of the coverage provided to their spouse. Because of this treatment, application of California AB 362 would be limited to a situation where an employer provides a federal tax gross-up to an employee who is in a California-registered domestic partnership. Such a gross-up, which would have been taxable under prior state law, is now no longer taxable in California. Employers in California will need to update their payroll and tax procedures accordingly. Employers both inside and outside of California that previously provided tax gross-ups may find it desirable to revisit their gross-up policies in light of the Windsor decision and the IRS guidance.