Ala. Code § 40-7-22

Having failed to procure on verbal or written demand from any delinquent his list of taxable property on or before the third Monday in January, the assessor shall ascertain from inquiry or otherwise the property and other subjects of taxation upon which such person is liable to be taxed and shall list and make return thereof upon the proper blank and note upon such returns the failure of the owner after notice to make such return and the accrual of a penalty of 10 percent of the taxes to be assessed thereon.