Your employer or the government will not apply for you. You have to do it or ask someone to help you.
You should apply for CPP disability benefits as soon as you:
There is no time limit to apply. But, CPP will only consider you disabled for a maximum of 15 months before you apply. Since CPP starts paying benefits 4 months after you become disabled, you can only get disability benefit payments for up to 11 months before the date you applied.
Usually, you continue getting CPP disability benefits until one of the following happens:
If you're 60 to 64 years old and getting a CPP retirement pension, you may be able to switch it to CPP disability benefits. See the step called Learn what your options are if you're 60 to 64 years old.
If your disability comes back after you return to work, you may be able to start getting CPP disability benefits again without going through the full application process. See the step called Find out how to restart your benefits if your disability returns after you go back to work.