Yes, you may be able to claim a portion of your mortgage interest if you have a home-based business in Canada. The CRA allows individuals to deduct a portion of their housing expenses, including mortgage interest if they use part of their home exclusively for business purposes. You can input your mortgage interest in the Business-use-of-home expenses subsection in the relevant business income section (T2125, T2121 or T2042).
To claim the deduction, you must meet certain criteria, such as using the designated area of your home regularly and exclusively for your business, and it must be your principal place of business or used to meet clients or customers. The amount you can deduct is based on the percentage of your home that is used for business purposes.
You cannot claim mortgage interest as a deduction on your income tax return. The CRA does not allow individuals to deduct mortgage interest expenses for their principal residence.