Yes you do. You have until May 31. However, you will not see the Presidential scholarship show up until approximately two weeks after you notify NMSC.
When will National Merit notify the University of my first choice selection?
Updated 02/05/2024 08:45 AM
Beginning in March, the National Merit Scholarship Corporation sends the Financial Aid Office a roster of all finalists who have selected USC as their first choice school. This roster is updated every two weeks.
If you have been admitted to USC and designate USC as your first choice school, please allow two weeks for your scholarship to be reflected in your financial aid summary.
ETA: Are you aware that there is a thread for Class of 2024 National Merit in the financial aid section of CC? Class of 2024 National Merit Discussion