CS Course Restrictions & Enrollment Caps

• Some seats will be reserved for incoming graduate, first-year, and transfer students. The instructor and advisors cannot give an override for these reserved seats. 
• If a section is marked "Closed," it is full at that time, and we will not provide overrides, even if Student Self-Service lists remaining seats.  Many CS courses have multiple sections/cross-lists that share all seats for the entire course.  If one section says there are remaining seats, those seats are likely occupied by students in another section. To know the actual seats remaining in a cross-listed course, you must look at the XL remaining number in Student Self-Service.
• For online sections, you must read the course notes in the online UIUC class schedule in Course Explorer to find out if you are eligible to register for the section. This includes City Scholar sections.
• The CS Academic Office does not create or manage wait-lists.
• Students in CS majors have specific sections to register for in CS 124, 128, 173, 225, & 233. All other students must register for the non-major sections, no exceptions. 
• CS 400-level courses (unless otherwise listed): If the course is cross-listed with another department, the CS Section will be restricted to students in CS programs and the cross-listed section to those within the cross-listed department, until restrictions are lifted.

Undergraduate students who wish to enroll in a graduate-level 4-credit section of a 400-level CS course or a 500-level CS course must receive approval from both the course instructor and the Siebel School of Computing and Data Science. To request approval, complete the Undergrad Application for Access to CS Graduate Sections.

• The Siebel School will begin reviewing petitions no earlier than three weeks before the start of the semester, as graduate students register later in the registration cycle. To ensure timely consideration, submit your petition by the Thursday before classes begin. Requests submitted after that date may be delayed and could require a late course change (add/drop) form.
• If a 400-level course also has an undergraduate section, you must remain enrolled in the undergraduate section while your petition is under review. If the graduate section is listed as Closed, the course has reached capacity, and additional students cannot be added.
• Instructor approval does not guarantee department approval.
• For summer courses, email instructor approval to undergrad@siebelschool.illinois.edu before the start of the summer term for full consideration.

Student Self-Service will not allow students to register for classes with overlapping meeting times. However, the CS Undergraduate Advising Office can sometimes provide an override if at least one of the courses is a CS course.  

If you do not follow the instructions given, your request will not be processed. Follow these instructions for the Time Conflict Override Request.

The Time Conflict Override portal will open at 8:00 am on March 31st and will close at 11:59 pm on the 10th day of classes.

Prerequisites are enforced for nearly all undergraduate courses, including 400-level CS courses. Students are responsible for meeting all course prerequisites before registering. The current updated list of enforced prerequisites on this Grainger web page.  A prerequisite override may be requested if you have additional proof that you have met the prerequisites or have other relevant background. Students who have transfer or proficiency credit that is not yet in the system should include proof of enrollment or proficiency credit in their petition. Students who have permission from an instructor to meet a prerequisite that they don’t have credit for will need to include a screenshot of an email from the instructor to document that permission.

• You will not be granted an override for missing coursework if you've already received an override for that missing prerequisite course in a previous semester (i.e. students need to take care of missing transfer/proficiency credit in a timely manner).
• Prerequisite overrides for courses taken at other institutions over summer or winter terms may not be entered until after all registration time tickets have passed, giving priority to students who already meet the prerequisites without needing an override.
• The Siebel School Undergraduate Programs office has final say in petition requests, even if you have faculty approval. 

For CS students to register for a CS 397 Individual Study, CS 497 Team Project, or CS 499 Senior Thesis, go to the CS Independent Study page and complete the form after speaking with faculty. After the petition has faculty and advising office approval, you will receive a CRN (course registration number) so that you can add the course.

• Be sure your credit hours are correct! If you are registering for CS 397, CS 497, or CS 499.
  If they are not, you can change the credit hours in the registration system before the add deadline. Email undergrad@siebelschool.illinois.edu for assistance if needed.
• Additional information about approval for CS 397, CS 497, and CS 499 is on the school's Policies and Procedures page.

• CS GRAD students: Most CS 400-level classes are available to register for 3 or 4 credit hours, if the 3 credit option is available for graduate students. Review info on the Office of the Registrar page for Changing Variable Credit Hours. CS 498 courses will have separate sections for 3 (if available) and 4 credit hours.
• Non-CS GRADS: CS will open GRAD seats to all GRADS by July 21, 2026.
  
• Non-CS GRAD students wanting 100, 200, or 300 level CS courses must submit a request here. Any request submitted after 9 am on the 10^th day (the add deadline) will not be reviewed/approved for the current semester.

Read this Important Information on how to access your CS Course Hosted on Coursera 

Current list of Fall 2026 Courses offered on Coursera available to on-campus UIUC students - restrictions may apply! See Course Explorer for each section for details (will be updated):

• CS 410
• CS 418
• CS 445
• CS 446 
• CS 447
• CS 463