Colorado allows for three types of solemnization: Religious, Civil, or Self. Regardless of which type is selected, witness’ signatures are not required on the marriage license. The ceremony must occur within 35 days after the license is issued in order for it to be lawfully valid.
Religious officiants must sign the marriage license and be recognized by the organization that ordained them to lawfully perform marriage ceremonies in Colorado. Out-of-state clergy do not need to be registered in Colorado, but must be authorized by their organization / entity to perform ceremonies in Colorado.
Judicial officiants must be recognized by the State of Colorado to perform marriages and must sign the marriage license as the Officiant with their title. Judges must be contacted for an appointment and cost.
A couple may choose to not have either a religious or civil ceremony and declare themselves legally married / joined in union. Friend or relatives can not solemnize a marriage or union unless authorized to conduct a religious or civil ceremonies in Colorado.