The employer must complete the I-9 within three business days of the hire (defined as the day the employee begins employment). 

The Immigration Reform and Control Act requires that anyone hired by a U.S. employer after November 6, 1986, complete an I-9 Form and present proof of U.S. citizenship, permanent residence status, or a valid passport along with a USCIS documents showing that employment has been authorized.

• An employer cannot knowingly hire an alien who is not authorized to be employed in the United States for the particular employment in question
• An employer cannot continue to employ an alien when it knows the alien is or has become unauthorized to work in that job in the United States
• An employer must comply with the rules of the employment eligibility verification system created by INA 274A(b) (Form I-9)

Students in F-1 status who have been authorized to engage in Curricular Practical Training (CPT) will need to present a Form I-20 authorizing details of the approved employment. 

 F-1 status who have been authorized for Optional Practical Training (OPT) will have an Employment Authorization Document (EAD) card issued by USCIS. This laminated card will include the individual's photograph and fingerprint and will provide additional proof of work authorization. 

J-1 Students on Academic Training will need to show a Form DS-2019 authorized for Academic Training as well as a letter from the RO/ARO at their school authorizing employer and job specific employment.