Regional Transmission Service Q&A
Transmission is the high-voltage lines that carry power long distances between power plants and the neighborhood substations that serve our customers. The RTS line item reflects only the actual cost of this service.
The average electric bill is made up of several parts. One of which is the cost for transmission service, labeled Regional Transmission Service (RTS). Because RTS only makes up one part of your total bill, the overall impact on bills is smaller, and will vary depending on customer class.
| CUSTOMER CLASS | RTS RATE Unit | RTS Rate jan-aug 2025 |
RTS FACTOR sept 2025 on |
% Change | rts component of overall bill* |
Overall Estimated Bill Impact over 2024 |
|---|---|---|---|---|---|---|
|
Residential
|
$/kWh | 0.04077 | 0.04055 | -0.5% | 22% | 0.9% |
| General Service | $/kWh | 0.03217 | 0.03196 | -0.7% | 20% | 1.0% |
|
Large General Service
|
$/kW | 10.72 | 10.66 | -0.6% | 25% | 0.7% |
|
Large General Service - |
$/kW | 6.49 | 6.42 | -1.1% | 24% | 6.7% |
|
High Load Factor |
$/kW | 11.93 | 11.87 | -0.5% | 31% | 0.7% |
| Lighting | $/kWh | 0.03533 | 0.03495 | -1.1% | 10% | 0.2% |
| Standby | $/kW | 8.08 | 7.98 | -1.3% | 73% | -12.8% |
*Percentage of total transmission to total annual bill.
Iowa – Regional Transmission Service ROE Refund
Background
The Federal Energy Regulatory Commission (FERC) has approved a refund for a portion of the costs Alliant Energy and its customers have paid to its transmission provider.
This is part of a complaint filed with FERC that transmission owners were charging too much for their Return on Equity (ROE) from November 2013 to February 2015, and September 2016 to October 2024.
As a result, money is being refunded to customers.
Did Alliant Energy overcharge customers?
No. Alliant Energy sets its Regional Transmission Service charge, based on expected costs from transmission owners. This charge is reviewed and approved each year by the Iowa Utilities Board. This refund is based on the costs charged by the transmission owners from November 2013 to February 2015, and September 2016 to October 2024.
Who gets a refund?
Electric customers in Iowa.
How will customers get the refund?
Refunds are included in the RTS rates shown in the table above for each customer class for September 2025 on.
How do you determine the refund amount?
The refund amount is based on how much each class of customers has already paid for transmission service. The amount for each class of customers is then split up based on billed energy or billed demand, depending on the type of customer.