HomeWattCost

Alliant Energy IA 400 vs 407

400 and 407 cost about the same for a typical Iowa home (within $1 a year). They stay within about 1% of each other at every level of use from 200 to 2,500 kWh a month, with the same daily pattern of use.

Utility Alliant EnergyTariffs checked 2026-10-31Typical use 848 kWh/mo, Iowa

Head to head

Scenario400407Cheaper
Typical home, per month$160$160Tie
All-in price per kWh18.8¢18.8¢Tie
Home + EV, charged at the cheapest hour$206$204407
Home + EV, plugged in at 6 pm$206$209400
Fixed charge$15.51$15.51

Typical home: Iowa 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 any hour on 400, 12 am on 407.

Month by month

Typical-home bill each month on each plan.

PlanJanFebMarAprMayJunJulAugSepOctNovDec
400$188$155$145$122$127$182$250$185$137$129$123$172
407$188$155$145$122$127$182$251$185$137$129$123$172

400: price by hour

July weekday.

Same price all day
19.4¢12a3a6a9a12p3p6p9p12a

407: price by hour

July weekday.

Off-peakPeak
17.1¢28.3¢17.1¢12a3a6a9a12p3p6p9p12a

400 or 407: common questions

Is 400 or 407 cheaper?

400 and 407 cost about the same for a typical Iowa home (within $1 a year). They stay within about 1% of each other 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, 407 gives the lower total ($204 against $206 a month).

What is the difference between 400 and 407?

400 is flat: the same price at every hour, with a fixed charge of $15.51 a month. 407 is time-of-use (summer weekdays: Peak 2 pm–7 pm; lowest price 7 pm–2 pm next day), with a fixed charge of $15.51 a month.

How the two plans work

400: Residential Service

  • One price per kWh at every hour: 19.4¢ in July and 16.0¢ in January.
  • Shifting use to other hours changes nothing on this plan; using less is the only lever.
  • Fixed charge: $15.51 a month.

407: Residential Time of Day

  • Peak 2 pm–7 pm on July weekdays; 5 of 24 hours carry the top price of 28.3¢.
  • The cheapest July weekday hour costs 17.1¢, so moving 1 kWh out of the top hours saves 11.2¢.
  • In January every hour costs the same (16.0¢).
  • Summer pricing applies Jun–Aug; winter pricing Sep–May.
  • Weekends differ: off-peak all day.
  • Fixed charge: $15.51 a month.

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