In addition to states having a minimum age requirement for two people to marry, or parental consent, some states also require either a blood test, a physical, or both.
Also a marriage license is required in most places. In some states there is a waiting period, and others not. Some marriage licenses also have an expiration date, so they can't be gotten too far in advance. To get a marriage license, official documents, such as birth certificates, are required. There is also usually a license fee.
You can check here for marriage license requirements by state. This is a general list and may not be current, it is only for guidance. Do check with the state in which you plan to marry. Also marriage laws can vary between in state marriages and out of state marriages.
If required, the minister, priest, justice of the peace, etc. will need to see the marriage license before they perform the wedding ceremony.
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