ST. LOUIS — Ameren Missouri says its customers in the state should see a slight reduction in their electric rates next spring.

The utility filed a proposal Friday with the Missouri Public Service Commission for a $1 million reduction in its revenues from rates. The company said a residential customer using 1,000 kilowatt hours a month would see a decrease of about 3 cents a month starting in May 2020.

It would be the second rate decrease for its 1.2 million Missouri customers in less than two years. A decrease of $167 million, or 6%, took effect in August 2018, with monthly savings of $6.21 for a residential customer using 1,000 kilowatt hours.

The company said the proposal would keep rates stable as it pursues $5.3 billion worth of upgrades to its system.