The U.S. Small Business Administration (SBA), in consultation with the Treasury Department, recently released additional PPP guidance and resources:  

Helpful Reminder for This Round of PPP

Make sure the PPP First Draw Loan number is included in the Second Draw PPP Loan application. As part of the Second Draw Borrower application, applicants must enter the SBA loan number of the First Draw PPP loan that was originated in 2020.

SBA loan numbers have the following format: eight numbers followed by a dash and then two more numbers.