000, 34 percent on e between $75,000 and $100,000, 39 percent on e between $100,000 and $335,000, and 34 percent on e between $335,000 and $10 million. Personal service corporations, like medical and law practices, pay a flat rate of 35 percent. In addition to the basic corporate tax, corporations may be subject to several special taxes.РCorporations must prepare an annual corporate tax return on either a calendar-year basis (the tax year ends December 31, and taxes must be filed by March 15) or a fiscal-year basis (the tax year ends whenever the officers determine). Most Subchapter S corporations, as well as C corporations that derive most of their e from the personal services of shareholders, are required to use the calendar-year basis for tax purposes. Most other corporations can choose