You can’t claim the full mortgage. But if you’re self-employed and work from home, you can claim a portion of the mortgage interest (not the capital repayment) as a business expense.
To calculate your claim:
- Area used for business: % of your home used for work.
- Time used for business: % of time that area is used for business.
Example:
- 10% of your home is used exclusively as a home office.
- You use it full-time for business.
- You can claim 10% of your annual mortgage interest.
Important:
- Keep records of mortgage interest and calculations.
- Claiming a home office may affect Capital Gains Tax (CGT) when selling the home.

