In pre-war days corporations paid a Dominion income tax of 15 per cent on net income, or 17 per cent if they consolidated their returns with those of subsidiaries. In the case of unincorporated businesses—partnerships and sole proprietorships—income tax was levied on the individual incomes of the persons participating in the business; no tax was levied on the business as a unit. Under present taxation schedules, the corporation income tax stands at 18 per cent; 20 per cent for companies making consolidated returns. Proprietorships pay higher taxes through the steeply increased individual income tax rates. And, finally, the excess profits tax has been superimposed on the previous tax structure.

The excess profits tax applies to all businesses, incorporated and unincorporated. In addition to the taxes assessed under the Income War Tax Act, they have paid up to the present either a flat rate on their total profits (in 1940, 12 per cent for all businesses; in 1941, 22 per cent in the case of corporations, 15 per cent in the case of other businesses) or 75 per cent on profits in excess of pre-war profits, whichever tax was the larger. The provisions listed in the Income War Tax Act for the exemption of educational, charitable, labour, farmers', and other such organizations apply equally to this tax. Otherwise it was assessed in 1940 and 1941 against every business in Canada having a profit, before any payments to partners, proprietors, or shareholders, of more than $5000, with the proviso that any part of the tax which would reduce the profit thus defined to less than $5000 was not to be paid.