Thanks for reaching out to us here. It's important that your employee calculations are accurate in QuickBooks Online Payroll. I'd be glad to help!
The Canada Pension Plan is a mandatory deduction for employees between the ages of 18 and 70. When CPP isn't calculated for an employee, you'll want to ensure they meet the criteria as set out on the CRA website. CPP contributions will stop being deducted when the employee's annual earnings have reached the maximum pensionable earnings, or the maximum employee contribution.
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