Mont. Code Ann. § 18-2-206

18-2-206 . Notice to contractor concerning subcontractor. (1) A person, firm, or corporation furnishing provender, provisions, materials, or supplies to be used in the construction, performance, carrying on, prosecution, or doing of any work for the state or any county, city, town, district, municipality, or other public body shall, not later than 30 days after the date of the first delivery to a subcontractor or agent of a person, firm, or corporation having a subcontract for the construction, performance, carrying on, prosecution, or doing of the work, give a notice of a right of action on the security.

(2) (a) The notice must be delivered personally or sent by certified mail to the contractor.

(b) The notice must be in writing and state:

(i) that it is a notice of a right of action on the security;

(ii) that the person, firm, or corporation giving the notice has commenced to deliver provender, provisions, materials, or supplies;

(iii) the name of the subcontractor or agent who placed the order or to whom the provender, provisions, materials, or supplies were delivered; and

(iv) that the contractor and the contractor's security will be held for the unpaid price if the supplier is not paid.

(3) To have a right of action against the contractor and the security under this part, a person, firm, or corporation shall give the written notice required by this section in substantially the form described in subsection (2). Any other type of actual or constructive notice is not sufficient.

(4) A suit or action may not be maintained in any court against the contractor or the security to recover for the provender, provisions, materials, or supplies or any part thereof unless the provisions of this part have been complied with.