Canada Emergency Wage Subsidy (CEWS) Calculator under Determine your eligible employees, 21 April 2020 CRA Webpage

Retroactively hiring and paying employees

Employees who have been laid off or furloughed can become eligible retroactively, as long as you rehire them and their retroactive pay and status meet the eligibility criteria for the claim period. You must rehire and pay such employees before you include them in your calculation for the subsidy.

What is eligible remuneration

Eligible remuneration includes amounts you paid an employee as salary, wages and other taxable benefits, fees, and commissions. These are amounts employers would be required to make payroll deductions on to be remitted to the CRA.

Severance pay and items such as stock option benefits or the personal use of a corporate vehicle are not part of eligible remuneration.