Mo. Rev. Stat. § 387.408

On behalf of a TNC driver, a TNC may charge a fare for the services provided to riders; provided that, if a fare is collected from a rider, the TNC shall disclose to the rider the fare, or fare structure on its website or on its digital network. If the fare is based on actual time and distance traveled, the TNC on its website shall also provide riders with the applicable time and distance rates being charged and the option to receive an estimated fare before the rider enters the TNC vehicle.