Acting Registrar-Recorder/County Clerk Dean Logan on Tuesday told county supervisors that his office would be ready to perform same-sex marriages June 16.
That is the earliest date on which the state Supreme Court's ruling allowing such marriages could take effect.
Logan said he would extend the corps of volunteers needed to officiate at marriages and would seek to open new offices to facilitate the ceremonies.
"We expect that when the decision goes into effect that there will be an initial peak in the volume of people coming into our office," he said. "We want to be sure we're prepared for that. We want to make sure we're staffed up for that."
Logan said he already had received a request from West Hollywood officials to have the county open a marriage-license office there.
Supervisors have asked Logan to convene an advisory group with gay community leaders to get a better handle on the number of couples expected to seek licenses.
Last week, justices struck down the state's ban on same-sex marriage in a broadly worded decision that would invalidate virtually any law that discriminates on the basis of sexual orientation.
Officials said it would be at least 30 days from the state Supreme Court's action before marriage licenses could be issued.
But opponents could ask the court to rehear the case. Even if the court declined, such a request could delay the effective date by up to 90 days.