Information for

CS course selection

Course selection (previously called “pre-enrolment”) is important to help us plan for upcoming terms.

Course selection

What is it? Course selection is when you make your best guess about which courses (if any) you want to take in a future term. This information is vital for our planning purposes. We need to know how many sections to create, how many professors and TAs to assign, etc.

When is it? Course selection occurs one term before you take courses. In the spring, you select courses for the fall. In the winter, you select courses for the spring, etc.

What are the benefits? Students who participate in course selection are automatically enrolled in those courses before the drop/add period begins. You have a very good chance of getting the courses you signed up for. If you miss course selection, you can only choose from the left-over courses.

CS policies

We can divide the time leading up to taking a course into the following time periods:

  1. Course selection: One term before you start courses, you choose the courses you want to take.
  2. Sectioning: The Registrar’s Office places you into specific course sections. 
  3. Drop/add period: Your opportunity to swap courses or sections to optimize your schedule. This starts several weeks before classes begin and ends after classes begin.
  4. Classes begin.

In Computer Science, we make modifications to the University’s procedures. In Step 2, we apply a departmental reserve of approximately 20% of the total enrolment number for the course to give advisors room to handle special cases.

For example, in the course schedule below, this course has 90 seats in each section and 13 seats are reserved for CS advisors to handle the special cases. If any section has a total enrolment of 76 or less then there potentially might be a spot available in that section. If all of the sections are showing as 77 or higher then that would mean there is no space currently available in the course.


We will remove the department reserve in the second week of classes after we have had time to deal with the special cases. Departmental reserves will be removed on the below dates and any remaining space will be available on a first-come-first-served basis only if the section isn't already at its enrolment cap.

  • CS 240/241/245/246/251 - January 12, 2018
  • All other CS courses - January 8, 2018

The special cases are:

  • Students who selected courses but something went wrong because of:
    • a time conflict
    • an academic enrolment block was applied after course selection
    • dropping or failing a course after course selection
  • Students who could not select courses because they:
    • recently transferred to CS
    • are international exchange students
    • were hospitalized
    • had an S&P or ELPE decision or related academic matters


Students who do not select their courses in advance and do not fall into one of the above categories:

  • will be required to wait until after advisors have handled failures and other legitimate situations
  • will compete on a first-come-first-served basis on Quest for any remaining spots
  • will not receive help getting into courses (e.g., overriding full sections, adding new sections, or enlarging existing sections)

Overrides are available during course selection just like during the drop/add period. See a CS advisor if you need an override to select a course.

Other notes

Department consent - for Winter 2018, some courses (CS 449/451/486/489 - LEC 003) have waiting lists. This is because the number of students who course selected the course is greater than the number of spots in the course. If you did course select any of these courses then you will be contacted at your uWaterloo email account if/when a spot becomes available. 

These changes only apply to CS courses. Math and elective course policies are set by other academic units.

We've observed some students selecting up to five courses and then dropping several at the beginning of the term. We view this as an abuse of the system. Selecting more than three CS courses may result in some of them being dropped before sectioning occurs.