Common Application vs. UCAS vs. OUAC: Which Platform Should You Use?

Ayushi
Aug 2
3 min read

Updated: Aug 26

When applying to universities abroad, choosing the right application platform is one of the first decisions you'll make. For international students targeting top destinations like the USA, UK, or Canada, three platforms dominate the landscape: the Common Application, UCAS, and OUAC.

Each has its own rules, deadlines, and structure—and using the wrong one could lead to delays or even disqualification. Here’s a quick breakdown of what each platform offers, their key differences, and which one is right for you.

What Are These Platforms?

Common Application (Common App)

A centralized platform used by over 900 colleges and universities in the USA and some institutions globally.
Offers the convenience of applying to multiple schools through one account.

UCAS (Universities and Colleges Admissions Service)

The official and mandatory application system for all undergraduate courses at UK universities.
Required for nearly all universities in England, Scotland, Wales, and Northern Ireland.

OUAC (Ontario Universities’ Application Centre)

A centralized portal for applying to public universities in Ontario, Canada.
Does not cover universities outside Ontario—you'll need other portals or direct applications for those.

Key Differences: At a Glance

Feature	Common App	UCAS	OUAC
Region	USA + some international	UK only	Ontario, Canada only
Number of Applications	Up to 20 universities	Up to 5 choices	Unlimited Ontario universities
Fee Structure	Platform is free; each university charges its own fee	Flat fee (£27.50 for 5 choices)	Fee per university
Essay Type	Personal, narrative-driven (650 words)	Academic and course-focused (4,000 characters)	Academic/program-focused
Supplemental Essays	Often required by individual colleges	Not required	Rare
Deadlines	Vary by college	Jan 31 (main), earlier for Oxbridge/Medicine	Varies by university
Extras/Activities Section	Yes — includes honors, work, leadership, etc.	No — academic focus only	No — mostly academic details

Which One Should You Use?

For U.S. colleges: Go with the Common App. It gives you access to hundreds of schools, including many top-tier ones, all in one place.
For UK universities: Use UCAS. While a few UK institutions are also on the Common App, UCAS is still the standard and most reliable route.
For Ontario, Canada: Use OUAC. This is the official platform for all public Ontario universities, including the University of Toronto, McMaster, and Queen’s.

Important: Never apply to the same university through multiple platforms (for example, both UCAS and Common App for the same school). Doing so can get all your applications rejected.

Application Essays: Not One-Size-Fits-All

Each platform asks for a different kind of essay:

Common App: More personal. You’ll be asked to tell your story, background, identity, or personal growth.
UCAS: Strictly academic. Why this subject? What makes you a good fit for the course?
OUAC: Varies slightly, but often focuses on your academic goals and program suitability.

Tailor your essay based on the platform. A strong Common App essay won’t work for UCAS and vice versa.

So… Which One Is Better?

There’s no single “best” platform—it depends on where you're applying.

Common App: Best for those focusing on U.S. universities or applying to multiple schools with varied requirements.
UCAS: Essential for the UK. Streamlined and efficient for up to 5 targeted applications.
OUAC: Mandatory for Ontario universities, and very effective for students applying in Canada’s most popular province.

If you're applying to universities in multiple countries, you’ll likely need to use more than one platform. For example:

Common App for the USA
UCAS for the UK
OUAC for Ontario, Canada

Conclusion

Choosing the right application portal is just the first step, but it’s a crucial one. Each platform has its own timeline, essay expectations, and strategy. By understanding their differences early, you’ll save time, avoid mistakes, and give yourself the best shot at getting into your dream university.

We understand that the application process can be overwhelming, so we're here to support you. The study abroad experts at Hello Study Global are there for you every step of the way. From preparing for entrance exams to college applications, we will guide you to success.

Feel free to reach out to us at Hello Study Global.