Does Carleton care how you rank it on OUAC?
The rank of your program choices is important. Your highest ranked program at Carleton will be considered first, but all program choices will be assessed. If you qualify for your first choice, you will receive an offer of admission for that program.
Your offer of admission will include information on the status of your other program choices. If you are eligible for another choice, and if there is space available in that program, you can be given an offer of admission. If a program becomes full, you will not receive an offer of admission, even if you were previously eligible.
Carleton University, quoted from the OUAC guide for guidance counsellors, September 2026 entry.
How that compares
Carleton does use your ranking among its own programs. Only 2 of the 21 Ontario universities that answer this do, so it is worth knowing before you assume the common rule applies.
17 universities do not consider your ranking at all
Algoma, Lakehead, Laurentian, McMaster, Nipissing, OCAD, Ontario Tech, Queen's, TMU, Trent, Guelph, Guelph-Humber, Waterloo, Windsor, Western, Laurier (Waterloo), York
1 university ignores it for offers but may use it for the waitlist
Ottawa
1 university ignores it except in one faculty
U of T (St. George)
This is what Carleton tells Ontario guidance counsellors; it is not published on their student pages. Rules like this change rarely, but confirm anything you are about to act on.