Idaho did not have a rate change on October 1, 2026. Idaho Power, which serves most of southern Idaho, changed rates on January 1 and again on June 1.
This article covers Idaho Power. It does not cover Avista or Rocky Mountain Power in Idaho, or cooperatives and municipal utilities.
Quick Summary
| Item | Effective | Change | Residential impact |
|---|---|---|---|
| General rate case | Jan. 1, 2026 | +$110 million (7.48%) | Not stated in source |
| Power cost and fixed cost adjustments | June 1, 2026 | +3.15% | About +$3.64 a month at 900 kWh |
| October 1, 2026 | n/a | No change found | n/a |
January 1: General Rate Increase
The Idaho Public Utilities Commission approved a $110 million increase, 7.48%, effective January 1, 2026. According to a summary of the company’s securities filing:
- Return on equity: 9.6%.
- Overall rate of return: 7.41%.
- Idaho rate base: about $4.9 billion.
An earlier report by the Idaho Press described Idaho Power’s proposal as a 17% increase for residential customers with more weight on fixed charges. We did not find how the approved 7.48% was spread across customer classes, so we give no residential dollar figure for January.
June 1: Annual Adjustments
Idaho Power files two adjustments each spring:
- Power Cost Adjustment (PCA). Reflects actual power costs. A good water year lowers it, because hydropower is cheap.
- Fixed Cost Adjustment (FCA). Applies to residential and small business customers and adjusts for changes in average use per customer.
Idaho Power says the combined effect on June 1, 2026 was a 3.15% increase, about $3.64 a month for a residential customer using 900 kWh.
What This Means for Homeowners With Solar
We did not verify Idaho’s current net metering or export credit rules for this article, so we give no export rates here. Ask your utility for its current solar tariff, and check how exported energy is credited before sizing a system. Fixed monthly charges are not reduced by solar.
If a rate case moves more of the bill into fixed charges, solar offsets a smaller share of it. Check the service charge on your current bill. Our solar payback guide shows how the retail rate and the export credit change the math.
What to Check on Your Bill
- The monthly service charge, compared with late 2025.
- The energy charge per kWh.
- The PCA and FCA lines, which reset each June 1.
For help sorting the lines on your bill, see our guide to reading your electric bill.
Limitations
The January figures come from a financial news summary of Idaho Power’s filing, not the commission’s order. We did not find the residential share of the January increase or the approved service charge.
Sources
- Idaho Power, “Annual Price Adjustments in Idaho”
- Investing.com, “Idaho Power receives approval for $110 million rate increase effective January 2026”
- Idaho Press, “Idaho Power proposal looks to increase residential power rates by 17%, focus on fixed charges”
Frequently asked questions
Did Idaho electric rates change on October 1, 2026?
We found no change on that date. Idaho Power's 2026 changes took effect January 1 and June 1.
How much did Idaho Power rates go up in 2026?
A general rate increase of 7.48% took effect January 1, 2026. On June 1, annual power cost and fixed cost adjustments added 3.15%, about $3.64 a month for a residential customer using 900 kWh.
What is the power cost adjustment?
An annual update that passes through the actual cost of power, including the effect of hydro conditions, fuel prices and market purchases. Idaho Power says it does not profit from it.
