Working in the US with a Fiancé Visa

Since your fiancée is permitted to spend 90 days in the US with a K1 fiancé visa before your marriage, he or she may also be permitted to work during this time. However, permission to work does not automatically accompany a K-1 visa. Your fiancée must file Form I-765: Application for Employment Authorization. You must submit this specific fiancé visa to the USCIS Service Center responsible for immigration issues in your area.
If your petition is approved, your fiancée may work for 90 days in the US, until the expiration of his or her K1 visa. If by this point you are married, your spouse may petition to have permission to work extended, using Form I-485, at the same time that he or she applies for LPR status.
Instead of applying so that your future spouse can work as soon as he or she enters the US on a K-1 visa, your fiancé visa lawyer may suggest that you wait to apply until after your marriage. This can reduce hassle and allow you spend more time and energy planning your wedding. Your K-1 visa lawyer, or immigration lawyer, may advise that you file both Form I-765 and Form I-485 together after your marriage, so that your fiancée can begin working at that point, rather than beginning work and then waiting for a renewal to be processed at the expiration of his or her fiancée visa.
Keep in mind that the children of your fiancée who are eligible to apply for K-2 visas and relocate to the US can also apply for permission to work.
 
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