Ontario Corporate Minimum Tax (CMT) before July 1, 2010

For tax years that end before July 1, 2010, Ontario Corporate Minimum Tax (CMT) applies to large corporations (or associated groups) with:

  • total revenue in excess of $10 million, or
  • total assets in excess of $5 million.

For tax years ending before July 1, 2010, the CMT rate is 4%. The gross CMT for a corporation is calculated by multiplying the CMT rate by the corporation’s adjusted financial statement income less CMT losses of prior years, allocated to Ontario.