The Washington Declaration of Mailing is a document that outlines the applicable laws and regulations governing the mailing of goods in the state of Washington. It is a document issued by the Washington State Department of Revenue and is required for any business or individual that mails goods within the state. The document serves as a reminder of the taxes and fees that must be paid when mailing goods within the state. The Washington Declaration of Mailing includes two types of declarations: 1. Retail Sales Tax Declaration: This type of declaration is used to declare the applicable state sales taxes on retail items and services. 2. Use Tax Declaration: This type of declaration is used to declare the applicable state taxes on goods and services that are used in Washington, but not purchased in the state.