To be honest, there is no fixed answer to your question. It all depends on an individual profile. I am assuming, you are thinking of Canada PR under Express Entry System. The minimum score required is six each in IELTS.But in actual, the minimum IELTS score required varies from profile to profile.
Example: If someone is 30 years old, has done Master level qualification, has 6 + experience and spouse is having five each in IELTS, this person will become eligible with six each.
On the other hand, if someone is 25 years old, has done Bachelor, has one year experience, single. He would not be eligible with six each result in IELTS under Express Entry Program.
https://www.quora.com/What-are-the-minimum-IELTS-bands-required-for-Canada-PR/answer/Sanjayai-Kapoor