The Iowa Verification of Master Address List On Paper (Creditor Matrix) is a list of addresses that have been verified by the Iowa Department of Revenue. This list is used by creditors to help them identify the correct contact information for a debtor, or person who owes money. There are two types of Iowa Verification of Master Address List On Paper (Creditor Matrix): the Iowa Individual Master Address List (IMAM) and the Iowa Business Master Address List (BMA). The IMAM contains information on individuals, such as name, address, Social Security Number, and date of birth. The BMA contains information on businesses, such as business name, address, and Federal Employer Identification Number. Both lists are updated annually and are available to creditors for purchase. The Iowa Verification of Master Address List On Paper (Creditor Matrix) is a valuable tool for creditors, as it helps them ensure that they have the most up-to-date contact information for debtors.