Mo. Rev. Stat. § 454.445: Fees for certain actions and documents, division not required to pay.

No deposit or other filing fee, court fee, library fee, or fee for making copies of documents shall be required to be paid by the family support division, or any attorney bringing action pursuant to a referral by the family support division, by any circuit clerk or other county or state officer for the filing of any action or document necessary to establish paternity, or to establish, modify or enforce a child support obligation.