Is electricity expensive in Idaho?

Idaho's residential average of 12.7¢/kWh is 33% below the U.S. average of 18.8¢/kWh, ranking 2 of 51 jurisdictions (1 = cheapest).

What's the cheapest electric water heater to run in Idaho?

Among currently certified models, the Friedrich PROH40 T2 FD400-15 costs the least at about $82 a year at Idaho rates (643 kWh/yr).

How does Idaho compare with other states?

The same median electric water heater costs $134 a year in North Dakota (the cheapest state) and $504 in Hawaii (the priciest). Idaho sits at $137.

Data through April 2026

Cost to run · Idaho · 12.7¢/kWh residential average

How much does it cost to run an electric water heater in Idaho?

$137/yr · median certified model

Idaho's 12.7¢/kWh rate undercuts the national average by 33%, so the typical certified electric water heater costs roughly $137 a year here instead of $204.

That makes Idaho the #2 cheapest of the 51 U.S. jurisdictions for running an electric water heater. Model choice matters as much as geography: at Idaho rates the most efficient certified model (Friedrich PROH40 T2 FD400-15) costs $82 a year while the most power-hungry (Smart Solar SSG2-ES 120) costs $221 — a spread of $139 every year. For reference, the national extremes are North Dakota (12.3¢/kWh) and Hawaii (46.6¢/kWh); the same median electric water heater would cost $134 and $504 a year there.

Idaho

$137

US average

$204

North Dakota

$134

Hawaii

$504

Median certified electric water heater (1,082 kWh/yr) per year, at each rate

The cheapest water heaters (electric) to run at Idaho rates

Top 10 by certified kWh, priced at 12.7¢/kWh
#	Model	kWh/yr	$/yr in ID
1	Friedrich PROH40 T2 FD400-15	643	$82
2	Rheem PROPH40 T2 RH375-15	643	$82
3	Rheem PROPH40 T2 RH400-15	643	$82
4	Rheem XE40T10H22U0	643	$82
5	Rheem XE40T10H22U1	643	$82
6	Richmond 10E40-HP515	643	$82
7	Richmond 10E40-HP5U15	643	$82
8	Ruud PROUH40 T2 RU375-15	643	$82
9	Ruud PROUH40 T2 RU400-15	643	$82
10	Eco-Logical OMNI-50HP1-1A	681	$86

Price any model at Idaho rates

Your rate, your numbers

Annual use (kWh)

Electricity rate

Per day: 38¢
Per month: $11.45
Per year: $137

1,082 kWh/yr × 12.7¢/kWh = $137/yr

Prefilled with the median certified electric water heater (1,082 kWh/yr). Every model page on this site carries its exact certified figure.

Questions, answered with the data

How much does it cost to run an electric water heater in Idaho?: About $137 a year for the median ENERGY STAR certified electric water heater, at Idaho's average residential rate of 12.7¢/kWh — that's $11.45 a month.
Is electricity expensive in Idaho?: Idaho's residential average of 12.7¢/kWh is 33% below the U.S. average of 18.8¢/kWh, ranking 2 of 51 jurisdictions (1 = cheapest).
What's the cheapest electric water heater to run in Idaho?: Among currently certified models, the Friedrich PROH40 T2 FD400-15 costs the least at about $82 a year at Idaho rates (643 kWh/yr).
How does Idaho compare with other states?: The same median electric water heater costs $134 a year in North Dakota (the cheapest state) and $504 in Hawaii (the priciest). Idaho sits at $137.

Keep digging

Rate source: US EIA, average residential price of electricity, see methodology.