Common Courses

The information contained on this page is for courses taken in modules within Science and/or the Schulich School of Medicine & Dentistry.

If you are a Science or BMSc (or Neuroscience) student and you are completing a module in another Faculty (e.g., Economics or Psychology in the Faculty of Social Science), you must also consult the other Faculty for information on how they address common courses in shared modules.

A common course is a course that is mandatory in both modules. Courses are not considered common between two modules until all choices from any picklists within the modules are exhausted, i.e., if the choice exists to take another course from a picklist, then another course must be taken (see Exception*).

Science/BMSc (including Neuroscience) students may double-count a maximum of 1.0 common course toward two modules.

When two modules contain more than 1.0 common course, the additional common course(s) must be distributed between the two modules as evenly as possible and substitute course(s) approved by the Department(s) offering the module(s) must be taken to maintain the number of courses required by each module. For example, if there are 2.5 common courses between two major modules, 1.0 can be counted toward both modules and 1.5 substitute courses must be taken (0.5 toward one module and 1.0 toward the other)


  • The requirements of each individual module, as specified in the Academic Calendar , must be met
  • Two modules cannot be completed in a degree if more than half of the courses in one module are common with courses in the other module (e.g., a Minor having 2.5 or more courses that are common with either a Major or Honours Specialization module cannot be completed in addition to the Major or Honours Specialization module)
  • The 1.0 double-counted courses will be selected first from courses required of both modules – only after required choices are exhausted can courses in lists of options be double-counted
  • The mark in a double-counted course will be used in calculating the average for both modules
    • When there are more than 1.0 common course(s), the 1.0 course(s) with the highest grade(s) will be used in both modules
  • In most cases, substitute courses will be selected from optional courses listed in the modules unless different substitutions are approved by the Department
  • Click here for a list of permitted substitute courses for modules in the Basic Medical Sciences
  • Approved substitute courses must meet the minimum mark requirement for the module/degree and are included in the average calculation for the module
  • Note that some modules specify that courses may not also be counted toward another module (for example, the Minor in Software Engineering) – in such cases, the common course policy does not apply and students must complete the full suite of courses specified for both modules

Exception*: If there is less than 1.0 common course between two modules, as defined above, then students are permitted to count up to 1.0 common course from picklists without exhausting the choice within the picklist. Students must consult with the Academic Advising Office for Science and Basic Medical Science students to ensure that they satisfy the exception.

How to Figure Out How Many Common Courses Are in Your Modules

  • Compare the required (mandatory) courses in your modules
  • Are there any courses that are common?
    • If yes, how many?
    • If more than 1.0, see next section on substitute courses

How to Determine Substitute Courses

Number of Common or Overlapping Required Courses Substitute Courses to Take
Zero None
0.5 None
1.0 None
1.5 0.5 course toward one of the modules
2.0 0.5 course toward one module and 0.5 course toward the other
2.5 1.0 course(s) toward one module and 0.5 course toward the other
3.0 1.0 course(s) toward one module and 1.0 toward the other
3.5 You cannot combine these modules if there are 3.5 or more common/overlapping required courses

Please see here for substitute courses for Basic Medical Science modules. For all other modules, please contact the department offering the module.

Examples of Modules with Common Courses

Example 1: Major in Medical Sciences plus Major in Biology

  • There are 2.5 common required courses: Biochemistry 2280A, Chemistry 2213A, Bio/Stats 2244A/B, and 1.0 from Biology 2290F/G, Biology 2382A/B, Biology 2581B
  • Students in this module combination are required to take 1.0 substitute course(s) toward one Major and 0.5 toward the other Major
  • For a worksheet on this popular module combination, click here

Example 2: Major in Medical Sciences and Minor in Biology

  • There are no required courses for the Minor in Biology (they are all options from a list)
  • However, Biochemistry 2280A, Chemistry 2213A, Bio/Stats 2244A/B, and 1.0 from Biology 2290F/G, Biology 2382A/B, Biology 2581B are required courses for the Medical Sciences Major
  • Therefore, students are required to take Biology 2483A/B, Biology 2601A, and one of Biology 2290F/G, Biology 2382A/B, Biology 2581B (whichever one is not being used toward the Medical Sciences Major) toward the Biology Minor
  • This means there is only 1.0 common course(s) for this combination and there is no need for substitute courses to be taken

Example 3: Major in Computer Science and Major in Data Science

  • There are 2.0 common required courses: Computer Science 2210A/B, 2211A/B, 2212A/B, and either Math 2155F/G or Computer Science 2214A/B
  • Students in this module combination are required to take a 0.5 substitute course toward one Major and 0.5 toward the other Major

Example 4: Major in Environmental Science and Major in Chemistry

  • There are zero common required courses for this module combination
  • Therefore, students can choose up to 1.0 optional courses from the Environmental Science Course List to be used toward both modules
      • For example, Chemistry 2272F and 3372F/G

For more information on Basic Medical Science Modules with Common Courses click here.