The biggest difference between the 2 is that IELTS is a paper-based exam and CELPIP is completely computer based. I have listed differences below for you to review and make an informed choice.
Note: CELPIP is available only in Canada, UAE, and US (NY). They will be starting soon in Philippines (Manila)
The interesting thing about the CELPIP test is the fact that the Listening and Reading sections contain a few unscored items that are used for test development and improvement. According to the CELPIP website, unscored items are indistinguishable from the regular scored questions and can be found anywhere within those two test sections.
CELPIP is slightly cheaper than IELTS, specifically in Canada.
Test and Result Times
The time it takes to complete all the sections of the CELPIP and IELTS tests is approximately the same: around 3 hours. However, the duration of the actual tests differs.
CELPIP is conducted in one 3-hour sitting. Since it is done on the computer, it is easy to keep track of how much time is left for each of the tasks. When going by sections, CELPIP seems to have longer Listening and Speaking sections and a slightly shorter Writing section. However, keep in mind that the CELPIP time breakdowns include the question, answer and transition times.
IELTS test takers, on the other hand, do not necessarily complete all the test components on the same day. Although three of the test sections are completed in the same test room, the Speaking section is done separately at a different time, day and possibly location (it can be taken up to a week before or after the other sections). There is also no automatic computerized time tracking, and the times presented in the table above may not include the transition times between the test sections and components.
The results take 13 calendar days for IELTS and 10-12 calendar days for CELPIP. If you are short on time and money is not an issue, CELPIP also has an express rating system: the score is available in three (3) business days for an extra $100 fee (plus applicable taxes).
Both IELTS and CELPIP were designed to measuring English language proficiency; the level of difficulty is approximately the same in both tests. However, certain sections can be viewed as easier or more difficult by individual test-takers. Here are a few differences that can be noted:
IELTS is a paper-based exam, while CELPIP is completely computerized. It may be more comforting for some people to do the writing section on paper and to keep track of their own time. Others, on the other hand, feel less pressure by the computer and prefer typing and being able to see their timing and word count. Also, the CELPIP test includes spell check in the writing component, which could be found useful by some applicants.
CELPIP test uses Canadian speakers, while IELTS test includes native speakers from Australia, Canada, New Zealand, the UK and US in their Listening section. Some non-native speakers may find the CELPIP Listening section more understandable. Also, when taking CELPIP, one is able to adjust the volume in the headphones for the Listening section to suit their needs.
IELTS Speaking section includes a live conversation with an examiner, while during CELPIP you record your voice on the computer. Some non-native speakers prefer talking to an examinator, while others feel more comfortable without the face-to-face interaction.