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Ameren Missouri 1(M) Overnight vs 1(M) Smart Saver

For a typical Missouri home using 1,039 kWh a month, 1(M) Overnight is cheaper by about $18 a year ($142 against $143 a month). 1(M) Overnight is cheaper or about the same at every level of use from 200 to 2,500 kWh a month, with the same daily pattern of use.

Utility Ameren MissouriTariffs checked 2026-10-12Typical use 1,039 kWh/mo, Missouri

Head to head

Scenario1(M) Overnight1(M) Smart SaverCheaper
Typical home, per month$142$1431(M) Overnight
All-in price per kWh13.6¢13.8¢1(M) Overnight
Home + EV, charged at the cheapest hour$163$1651(M) Overnight
Home + EV, plugged in at 6 pm$180$2051(M) Overnight
Fixed charge$9.19$9.19

Typical home: Missouri average use by month (EIA), shaped hour by hour (NREL ResStock), before taxes. EV: Tesla Model Y Long Range AWD, 1,000 miles a month; cheapest start 12 am on 1(M) Overnight, 12 am on 1(M) Smart Saver.

Month by month

Typical-home bill each month on each plan.

PlanJanFebMarAprMayJunJulAugSepOctNovDec
1(M) Overnight$145$120$100$85$94$195$245$235$175$90$91$125
1(M) Smart Saver$147$122$101$86$94$198$247$238$177$91$93$127

1(M) Overnight: price by hour

July weekday.

Off-peakPeak
8.3¢19.4¢8.3¢12a3a6a9a12p3p6p9p12a

1(M) Smart Saver: price by hour

July weekday.

Off-peakMid-peakPeak
8.7¢13.2¢41.5¢13.2¢8.7¢12a3a6a9a12p3p6p9p12a

1(M) Overnight or 1(M) Smart Saver: common questions

Is 1(M) Overnight or 1(M) Smart Saver cheaper?

For a typical Missouri home using 1,039 kWh a month, 1(M) Overnight is cheaper by about $18 a year ($142 against $143 a month). 1(M) Overnight is cheaper or about the same at every level of use from 200 to 2,500 kWh a month, with the same daily pattern of use. Adding an EV driven 1,000 miles a month and charged at each plan’s cheapest hour, 1(M) Overnight gives the lower total ($163 against $165 a month).

What is the difference between 1(M) Overnight and 1(M) Smart Saver?

1(M) Overnight is time-of-use (summer weekdays: Peak 6 am–10 pm; lowest price 10 pm–6 am next day), with a fixed charge of $9.19 a month. 1(M) Smart Saver is time-of-use (summer weekdays: Mid-peak 6 am–3 pm, Peak 3 pm–7 pm, Mid-peak 7 pm–10 pm; lowest price 10 pm–6 am next day), with a fixed charge of $9.19 a month.

More Ameren Missouri comparisons

How the two plans work

1(M) Overnight: Overnight Savers

  • Peak 6 am–10 pm on July weekdays; 16 of 24 hours carry the top price of 19.4¢.
  • The cheapest July weekday hour costs 8.3¢, so moving 1 kWh out of the top hours saves 11.1¢.
  • January weekdays range from 7.3¢ to 11.3¢.
  • Summer pricing applies Jun–Sep; winter pricing Oct–May.
  • Fixed charge: $9.19 a month.

1(M) Smart Saver: Smart Savers

  • Mid-peak 6 am–3 pm, Peak 3 pm–7 pm, Mid-peak 7 pm–10 pm on July weekdays; 4 of 24 hours carry the top price of 41.5¢.
  • The cheapest July weekday hour costs 8.7¢, so moving 1 kWh out of the top hours saves 32.8¢.
  • January weekdays range from 7.3¢ to 22.7¢.
  • Summer pricing applies Jun–Sep; winter pricing Oct–May.
  • Weekends differ: Mid-peak 6 am–10 pm.
  • Fixed charge: $9.19 a month.

Your own pattern of use decides the winner: compare every Ameren Missouri plan on your usage, or see all Ameren Missouri plans, sources and peak hours.