The personal property tax bill is based on the assessed value of a business's tangible business personal property (mostly furniture, fixtures, and equipment) as determined by the State Department of Assessments and Taxation ("SDAT"). SDAT's assessment is based upon a personal property return which a business in Maryland is required to file each year. This return, due April 15, must report the cost basis and year of acquisition of the personal property owned or used by the business as of January 1st of that year. If a business fails to file a return, SDAT may estimate an assessment for the property. The tax collector applies the local property tax levy rate to the assessed value, calculates the tax, and mails the business a bill.