Facilities worldwide that manufacture, process, pack or hold food intended for consumption in the United States are required to register with the U.S. Food and Drug Administration (FDA).  The agency has mandated facility registration since the Bioterrorism Act of 2002, but imposed additional requirements after the passage of the Food Safety Modernization Act (FSMA).
Under the food safety law enacted in 2011, both domestic and foreign facilities must update their facility registration during the final quarter of every even-numbered year.  Facility registration or renewal should be completed this year by December 31.   

To explain and clarify the requirements, the FDA published a final rule for food facility registration in July 2016, and recently issued an updated version of a guidance that describes the requirements in a question-and-answer format. 
FDA issued the final rule this year to formalize the facility registration requirements for domestic and foreign facilities that were in effect since 2011 under FSMA.  The final rule established new requirements for the identification of activity types conducted at a facility, use of a unique facility identifier (UFI), and the electronic submission of registration by January 4, 2020. 
The registration process requires the acceptance of certain provisions, including permitting FDA to inspect the facility, and a requirement to provide the email address of the contact person.  To improve the accuracy of registration information, the rule contained a new requirement for a Unique Facility Identifier (UFI) and the FDA verification of UFI prior to confirmation of registration.  If food is imported from a foreign facility without registration, the FDA guidance states the food must be held at the port of entry.  The shipment would not be delivered to the importer, owner, or consignee of the food until the foreign facility is registered.

Source:  U.S. Food and Drug Administration