I-9 Employment Authorization
Federal law requires all employers to complete an I-9 form to verify an employee’s identity & work authorization. UW-Madison and some UW System campuses use an online system to complete I-9’s electronically. The I-9 system can be accessed using your smart phone or other mobile device in addition to a computer. Your HR will email you a link to the electronic I-9 system and login instructions on or before your start date. If your UW campus still uses paper I-9s, information on how to complete the paper form will be provided to your from your HR.

You (the employee) must complete Section 1 of the I-9 (paper or online) on or before your first day of work for pay.  If you are currently outside the U.S. and have not yet begun working for the UW, you will not be able to complete Section 1 until you have arrived in the U.S. 

Employers (your hiring unit or department) must complete Section 2 of the I-9 within 3 business days of your first day of work for pay. Business days are considered Monday through Friday only. In order for your employer to complete Section 2, you must present original work authorization documents to your employer no later than 3 business days after your start date. A full list of acceptable documents can be found here. According to federal law, employers cannot tell you which documents to bring. 

Reverifying your work authorization
Since your work authorization is for a limited duration, you will need to re-verify your employment eligibility each time you obtain an extension or change of immigration status. To re-verify your employment eligibility, simply provide your updated original work authorization documents to your hiring unit or department. They will complete the re-verification and/or provide you with any further directions at that time. 
Additional Resources:
UW-Madison I-9 Information
University of Wisconsin System I-9 Verification Policy
UW-Madison I-9 Verification Policy
I-9 Central