Building a Strong Supplementary Application
How to approach the AIF, personal statements, and interviews programs actually read.
For Canada's most competitive programs — Waterloo engineering and CS, McMaster Health Sciences, Queen's Commerce, Ivey AEO, UBC's Sauder — grades alone aren't enough. The supplementary application is where you separate yourself. Here's how to approach it well.
What a supplementary application is
A supplementary application is any part of your admission file beyond your grades — a written statement, a list of activities, an interview, a portfolio, or a reference. Different programs ask for different things, but they all share one purpose: to see evidence of who you are and what you've actually done, not just your marks.
The Ontario tools you'll likely use
In Ontario, the two you'll hear about most are the OUAC (which covers applications and supports some supplementary components) and the Waterloo AIF. For Fall 2027, Waterloo's AIF has four short written questions (150 words each) plus a section listing your activities and hours. Waterloo Engineering also requires a short recorded online video interview, and Math/CS applicants fill in a supplementary information form. McMaster Health Sciences uses its own supplementary application, due in early to mid-February, which is a separate step from Casper. Casper, now run by Acuity Insights, is used by McMaster Nursing but not Health Sciences. Queen's Commerce (and Health Sciences and Nursing) asks for one written response and one video response, due February 15. Ivey AEO asks for awards, activity essays with references, and a recorded video interview. Formats change from year to year, so read exactly what each program asks for in your cycle.
Show evidence, not adjectives
The most common mistake is telling — 'I'm passionate about engineering' — instead of showing, 'I led a six-person robotics team that placed top ten at VEX provincials.' Admissions teams read hundreds of applications; concrete, specific evidence is what they can actually assess. Every claim should be backed by a concrete role, timeframe, and outcome.
Quality and depth over a long list
A spreadsheet of thirty shallow activities is weaker than three activities where you had real responsibility over several years. Depth signals commitment and growing leadership. The Extracurriculars explorer and Your Extracurriculars dashboard help you structure exactly this — role, hours, commitment level, and progression.
Start the supplementary early
Because supplementary deadlines (usually mid-January to mid-February) can be earlier than you expect, and because strong answers are a product of reflection more than writing skill, start gathering your activities, contest results, and best stories in the fall — well before the main application deadline. Then the shorter writing task is mostly revision, not first draft.
Key Takeaways
- Supplementary apps are where competitive programs separate top applicants.
- AIF, statements, portfolios, and interviews all reward concrete evidence over adjectives.
- Deep, multi-year involvement beats a long, shallow list.
- Start assembling your activities and stories in the fall — deadlines arrive faster than you expect.