If you want to qualify for Express Entry, then you must first qualify for one of the economic programs such as Federal Skilled Worker Program (FSWP), Canadian Experience Class (CEC) or Federal Skilled Trades Program (. Your language score must meet the threshold of any of those programs you are trying to qualify for.
CEC has two thresholds: CLB7 for skill types 0 and A. CLB6 for skill type B.
FSWP’s threshold is CLB7
FSTP under CLB: L: 5, R: 3.5, W: 4, S: 5
For English, results from both the CELPIP (Canadian English Language Proficiency Index Program) and the IELTS (International English Language Testing System) tests are accepted.