Metadata
Title
CS course enrollment during Add/Drop period
Category
general
UUID
9a55c9f15d854e12904c7ab45ca61ded
Source URL
https://cs.uwaterloo.ca/current-undergraduate-students/majors/cs-course-enrollme...
Parent URL
https://cs.uwaterloo.ca
Crawl Time
2026-03-18T05:13:30+00:00
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CS course enrollment during Add/Drop period

Source: https://cs.uwaterloo.ca/current-undergraduate-students/majors/cs-course-enrollment Parent: https://cs.uwaterloo.ca

In Computer Science, CS advisors have made modifications to the University’s procedures during the Add/Drop period for CS courses only. If you are not able to enroll into a CS course, then the information below may answer your questions.

If you want a non-CS course (e.g., Math, electives, etc.), then please contact the department's advisor/staff of that course for an override. CS advisors are not able to override students into non-CS courses.

IMPORTANT DATES:

Thursday, May 14, 2026 Enrolment caps are restored
Tuesday, May 19, 2026 Reserves removed (except for SE and GBDA sections) Instructor consent is added to select courses
Wednesday, May 20, 2026 Non math students can enroll into CS 245/246 (space permitting) Eligible Engineering students can enroll into select CS courses

[Department Consent Error and Waitlisted Courses

What courses are currently waitlists?](https://cs.uwaterloo.ca/current-undergraduate-students/majors/cs-course-enrollment/department-consent-course-waitlists)

What do I do if...

Specific cases

Understanding course enrollment

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

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

Remote video URL

View "Course enrolment during the add/drop period" on YouTube

[Registrar's Office

What is the Add/Drop Period?](https://uwaterloo.ca/registrar/registering-courses/dropadd-period)

[Adding classes during enrollment

How do I add a class on Quest?](https://uwaterloo.ca/quest/help/students/how-do-i/add-classes)

Overrides and special cases

In general, we do not override prerequisites for our courses.

Even if you meet the prerequisites but run into another error, we will not override you into any CS courses unless you meet our special case guidelines listed below:

  1. Students who participated in course selection, but something went wrong because of:
  2. enrolment capacity in a course (please review more information regarding waitlists)
  3. a time conflict
  4. an academic enrolment block was applied after course selection
  5. dropping or failing a course after course selection
  6. Students who could not select courses because of:
  7. a recent transfer to CS
  8. their status as international exchange students
  9. hospitalization
  10. an S&P or ELPE decision or related academic matters

Please note that courses that have a waitlist will not be available on a first-come-first-serve basis unless department consent has been removed. Department consent will only be removed once we have exhausted the waitlist.

If you did participate in course selection you are likely already on the waitlist for the course.

The course is full, what do I do?

During the Add/Drop period, we drop the enrolment caps by approximately 15% of the total enrollment number for the course to give advisors room to handle special cases. We will return the enrollment caps to their actual size during the second week of classes after we have had time to help students that fall under our special cases.

See above for the date when enrollment caps will be restored (exact time unknown but usually during business hours).  After the enrolment caps are returned to their actual size, the remaining space may continue to have reserves on the course, which will be removed usually the following day.

If you get a “department consent” error when adding a course on Quest, it’s likely that the course has a waitlist. You will not be able to add that course unless given consent by a CS advisor if this occurs after the waitlist has been exhausted or you are a special case).

[Check for dates and

Currently Waitlisted Courses](https://cs.uwaterloo.ca/current-undergraduate-students/majors/cs-course-enrollment/department-consent-course-waitlists)

[Avoiding Department Consent Errors

Participating in Course Selection](https://cs.uwaterloo.ca/current-undergraduate-students/majors/cs-course-selection)

Reserve error

If you get a "reserve error" when adding a course on Quest, this means that a portion of the class’s enrollment is reserved for a particular group of students and you don't meet the reserve capacity requirements for that course.

Tip: You can tell that a course has set aside a number of seats for a particular group of students on the Schedule of Classes, directly beneath each section that has a reserve capacity assigned.

See above for the date when reserves will be removed by the Registrar's Office. The exact time is unknown, but the reserve restriction is usually removed during normal business hours. Once reserves are removed, then you can enroll into the course using Quest. Note that spaces in the course will be available on a first-come-first-served basis if the class section isn't already at its enrollment capacity.

During the second week of the term (see above for exact date), Instructor Consent will be applied to our project based courses (e.g., CS 346, 445, 446, 449, 493, and 494). A student wishing to enroll into one of these courses would need to contact the instructor first and meet their conditions for enrollment (e.g., the student may need to find a group before they can enroll). If the student is able to meet these conditions and if the instructor consents, then the instructor will contact the CS advisors directly so that we may override the student into the course.

I'm in the AI and/or DHW specialization and want an Engineering course. What do I do?

During the course selection period:

Since Engineering needs to prioritize their own students, you won’t be able to course select for Engineering courses during this period. We will not know whether Engineering will have space for CS students until the add/drop period. For this reason, we recommend the following for your next steps:

During the add/drop period:

I'm in Math and I want CS245 or CS246. What do I do?

Math students are able to take CS 245 and CS 246, but most seats (~85%) are reserved for CS students. The remaining seats (~15%) for Math students fills up quickly, so not all Math students will get into these classes even though they chose CS 245 and CS 246 during course selection.

Math students won't be able to add the courses during the Add/Drop period because they don't meet the reserve requirements of being a CS student. CS advisors will not be able to override Math students even if they course selected for CS245 and/or CS246, or need the course to raise their average to transfer into CS.

That said, the reserve for CS courses will be removed shortly after classes start. When reserves are removed, Math students can add CS 245 and/or CS 246 via Quest on a first come, first served basis.

Remote video URL

View "I’m in Math; how do I enroll into CS 245 and CS 246?" on YouTube

I'm in Engineering and I want a CS course, what do I do?

An Engineering student (excluding SE students*) may take CS major or non-major courses as defined below.

*Like CS students, SE students are able to take CS course so long as they meet the course prerequisites and course enrolment requirements.

Course Equivalents

We recognize the following specific pairs of engineering courses as equivalents that can be used towards our prerequisites (having one course doesn’t grant credit for anything).1

List A: CS 115 and CS 116 List B: CS135 and CS136
- GENE 121 + MSCI/MSE 240 - MTE 121 + MSCI/MSE 240 - MSCI/MSE 121 + MSCI/MSE 240 - NE 111 + MSCI/MSE 240 - ECE 150 + ECE 250 - SYDE 121 + SYDE 223 - GENE 121 + MTE 140 - MTE 121 + MTE 140 - BME 121 + BME 122

1This list is up-to-date on the day published. We reserve the right to update these details at any time.

Taking courses with the pre-requisites

If you have the prerequisites for a course, either directly or indirectly using this table, then you are allowed to take that course. If you have the prerequisites, then you are allowed to take CS Minor courses without further restriction.

Taking courses without the pre-requisites

If you are missing prerequisites for a course, we will allow you to enroll if you meet all of the following criteria:

The following restrictions apply:

If you are using this rule to take a CS Major course, then the following additional restrictions apply: