Can I deduct mortgage interest paid on my primary residence in Canada?

Yes.  If you are a US resident filing a form 1040, you can deduct the interest on your Canadian Primary Residence in you are taking the itemized deductions instead of the standard deduction. 

Itemized expenses include mortgage interest, gambling losses up to winnings,  charitable contributions, state and local taxes up to $10,000, medical expenses in excess of 7.5% of your AGI and casualty and losses in excess of 10% of you AGI with the first $100 not counting towards the loss.  

Then your total itemized expenses would need to be greater than your standard deduction below in order to benefit from your expenses. 

The 2024 Standard Deductions are as follows:

• Married Filing Joint (MFJ)              $29,200
• Married Filing Separate (MFS)      $14,600
• Head of Household (HOH)             $21,900 
• Single                                                 $14,600                                

Blind or over 65 and MFJ or MFS add $1,550

Single or HOH if blind or over 65 add $1,950

Standard versus Itemized Deduction