As we are past the final remittance date for 2015 payroll you will have to file an amended T4 with the CPP reported and pay the outstanding amount. As the payment is late there will probably be a penalty assessed.

You will have to pay both the employee and employer CPP when you file the amended T4. If the employee still works for you, you are allowed to recover the employee share. Note, however, that you are not allowed to recover a whole year's CPP on one paycheque - I believe the rule is that you can double up the CPP deduction each cheque, but no more. Also, be sure you do this properly - the CPP you are recovering needs to be set up as a loan, because your 2016 payroll will be a real mess if you double up in the actual CPP field.

@C White is correct. Follow - sagecity.na.sage.com/.../93920

OK. Thank you very much.
The problem is, that we mailed out T4's already.
What can we do now?

Thank you in advance!

If you already mailed out T4's, then there may be very little that you can do. You may want to contact the CRA and ask if it would be an option to amend some T4's