In order for TurboTax to claim your employment expenses, please go to your T4 Employment Income on TurboTax, scroll down to the bottom of the page, where you will be asked "Will you claim employment expenses for working at home due to COVID-19 for income on this T4?", say YES to this question.
For more information, please follow these links
How do I claim home office expenses?
Am I eligible to claim employment expenses due to COVID-19?
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