The duties and responsibilities of a Billing Specialist include sending invoices and account updates to clients, receiving, sorting, and tracking incoming payments, addressing and resolving client questions and issues relating to invoices, and providing regular, accurate reports of billing data. A billing clerk job is to create bills and credit memos, update customer files, and send invoices and payment reminders to consumers. Customers are their major point of contact outside of work. They interact with the shipping and order entry departments on a day-to-day basis.