An organization that hires and employs people in two or more States. The multistate employer conducts business within each State and the employees are required to pay taxes in the State where they work. As with single-state employers, multistate employers are required by law to report all new hires to the State Directory of New Hires (SDNH) operated by their State government. However, unlike single-state employers, they have the option to report all of their new hires to the SDNH of only one State in which they do business rather than to all of them.
Source: Office of Child Support Enforcement.