A marriage certificate is an official document stating that two people are legally married to one another. Marriage certificates are issued by state or local government officials after couples have officially wed and filed their completed marriage license.
So, a marriage certificate is not the same thing as a marriage license. A marriage license is a document issued by the county clerk stating that two individuals are legally able to marry one another. After the wedding ceremony, the couple and their official must sign the marriage license and submit it to the appropriate government agency. The marriage will be recorded and a marriage certificate issued.
A marriage certificate can be used as proof of a legal name change or as evidence during divorce proceedings or paternity/custody cases. If you need a certified copy of your marriage certificate, you can apply for one at the Vital Records Office in the state where you got married.