Mont. Code Ann. § 10-4-203

A provider or seller responsible for the collection of the fee imposed by 10-4-201 shall keep records, render statements, make returns, and comply with rules adopted by the department of revenue with respect to the fee. Whenever necessary in the judgment of the department of revenue, it may require the provider, seller, or subscriber, as defined in 10-4-101 (21)(a), to make returns, render statements, or keep records sufficient to show whether there is liability for the fee.