Applying for STEM Extension is a two step process.
1. The first step is to apply for a STEM Extension recommended form I-20 by submitting the STEM Extension request e-form. Please review the following link, which lists required documentation:
Once you have applied for the STEM Extension form I-20, please allow five to seven business days for processing.
2. The second step is to apply to USCIS for an Employment Authorization Document (EAD). This can be done either via mail, or via the USCIS online I-765 filing system.