Mo. Rev. Stat. § 115.345: Notice of offices for which candidates are to be nominated, when sent — election authority to publish notice with filing date.

1. Not later than the third Monday in December immediately preceding the primary election, the secretary of state shall prepare and transmit to each election authority a notice, in writing, designating the offices for which candidates are to be nominated at the primary election.

2. Upon receipt of notice, the election authority shall publish the notice and the date by which candidates must file for such offices in a newspaper of general circulation in its jurisdiction.