Ameren wants a rate hike. Ameren is asking Missouri regulators to raise electric rates by $376 million, or 14.6 percent, calling the increase is necessary for reimbursement of infrastructure upgrades, higher fuel costs and environmental improvements. The average residential customer would see their monthly billsrise about $14. says customers have repeatedly called reliability their top priority, and infrastructure improvements have reduced the frequency of outages by 27 percent since 2006. The Missouri Public Service Commission approved a seven percent rate increase for Ameren about six months ago.