Ala. Code § 40-21-3

Every person, firm, or corporation whose property is required by this title to be assessed for taxation by the Department of Revenue and not herein otherwise specifically required to make reports to the said department shall, on or before March 1 of each year, make a report of all its property of every nature and character whatsoever and such other and further information upon such forms and in such manner as may be required by the Department of Revenue.