All sales by or uses by the United States or an agency or instrumentality of the United States are exempt from the sales tax and use tax.
Mont. Code Ann. § 15-68-206, under Nontaxable Transactions and Exemptions.
Mont. Code Ann. § 15-68-206
All sales by or uses by the United States or an agency or instrumentality of the United States are exempt from the sales tax and use tax.