Washington Revised Code Title 82. Excise Taxes § 82.08.0268. Exemptions--Sales of machinery and implements, and related parts and labor, for farming to nonresidents for use outside the state

(1) Machinery and implements for use in conducting a farming activity;

(2) Parts for machinery and implements for use in conducting a farming activity; and

(3) Labor and services for the repair of machinery, implements, and parts for use in conducting a farming activity, when such machinery, implements, and parts will be transported immediately outside the state. As proof of exemption, an affidavit or certification in such form as the department of revenue shall require shall be retained as a business record of the seller.