In 2020, at the beginning of the Covid-19 pandemic, California Governor Gavin Newsom signed an executive order (N-58-20) to allow couples to get marriage licenses and have their marriages solemnized (in a ceremony) online, via live videoconferencing. The original order was extended (in Executive Order N-71-20) until the end of California's Covid-19 State of Emergency.
On February 28, 2023, Governor Newsom issued a proclamation terminating the State of Emergency. This means that, for now at least, Californians must get their marriage licenses and have their marriage ceremony in person—unless they qualify for one of the limited exceptions.
Under current California law, couples must show up in person at the county clerk's office to get a marriage license. There are two exceptions:
(Cal. Fam. Code §§ 359, 420, 426 (2023).)
California doesn't require any particular form or procedure for a wedding ceremony (called "solemnization" of marriage in state law), but the law does require that couples appear in person before an officiant (and at least one witness) to declare that they take each other as spouses. Military members serving in a conflict may have an attorney appear for the solemnization on their behalf. But there's no "physical inability" exception for the requirement to have the marriage solemnized in the physical presence of the officiant (presumably because the officiant could come to person who can't travel). (Cal. Fam. Code §§ 420, 422 (2023).)