Home office expense claim due to COVID-19

Home office expenses are claimed on the employment expense claim form, CRA Form T777 with their eligibility for the deduction provided by the employer on CRA Form T2200. The T2200 also outlines the eligibility for an employee to claim other employment expenses including unreimbursed auto expenses.
Home office expenses are deductible provided the employer states that you had to use a home office. This is generally the case where you are working in an area where your employer does not maintain an office where you can easily go to and you require a home office.
Because individuals are working from home during COVID-19, CRA has come out with a simplified method. One may use the simplified method if you worked more that 50% of the time from home for at least 4 consecutive weeks in 2020. The simplified method allows a flat claim of $2 per day to a maximum of $400.

The simplified expense claim

The simplified claim requires the T777S and the T2200S. The T2200S should be provided to you by your employer and retained should CRA with to verify your claim.
One may make a claim using the detailed method which requires both T2200S and the T777S with option 2 completed on the form.
Here one would itemize eligible expenses based on space used in your home and time using that space, similar for a home office claim without COVID-19. Eligible expenses may include such things as rent, and utilities, maintenance attributable to space used plus unreimbursed office supplies and phone usage including use of basic cell service and long distance calls for employment. For employees who are commission- based, the claim may include portion of insurance, property taxes and equipment lease payments, but not mortgage interest, CCA or capital expenditures.

Other expenses claim

The home office claim is limited to your employment income (net of deductions for registered pension plan, contributions, union, or professional dues), with any excess available for carryover to a subsequent taxation year.
If you are also claiming auto expenses, then you must use the regular forms T777 and T2200 for your home office claim. Home office expenses for employees – Canada.ca
Reference may be made to CRA publication T4044 and the CRA website at Home office expenses for employees – Canada.ca and How to claim – Home office expenses for employees – Canada.ca for additional information.