Wisconsin bi-annual rate filing for 2026 and 2027

On March 31, 2025, we filed our biennial rate review application with the Public Service Commission of Wisconsin (PSC) covering years 2026 and 2027. Guided by our strategic plan and purpose-driven strategy, our filing consists of investments in traditional, new and renewable energy sources. Collectively, this positions us to deliver what matters most – a responsible energy future that is cost-effective, reliable and safe.

If approved by the PSC, Alliant Energy’s rate and fuel cost adjustments would equate to:

Average residential electrical monthly bill increases of about $6 a month in 2026 and another $8 a month in 2027.
About $3 a month to the average residential natural gas customer’s bill in 2026, and about $3 a month in 2027.

Pending PSC approval, we anticipate changes to our electric and natural gas base rates for all retail customers in Wisconsin will take effect January 1, 2026 and January 1, 2027. As part of its review process, the PSC will schedule technical and public hearings. For specific information about the hearing schedule or regulatory process, call the PSC at 800-225-7729 or visit psc.wi.gov and search for docket number 6680-UR-125.

Key components

Cost-effectively advancing responsible energy solutions: Investment in a combination of traditional, new and renewable energy sources positions us to meet customer demand – today and long into the future.

Building a strong, reliable, resilient, safe energy future: Positions us to meet growing energy demands, maintain best in class reliability and promote long-term energy security.

Powering customers forward and expanding energy options: A variety of new innovative customer-focused options are included, such as new Time of Use and demand-response programs, EV rebates, and offerings to help low- to moderate-income customers with their utility bill.

Prudent, long-term planning supports community and business growth: Ongoing energy planning supports regional growth strategies designed to attract high-tech industries and other energy-intensive businesses that drive job creation and economic growth. This in turn helps to spread fixed costs over a larger base, making energy more affordable for all.

Frequently asked questions

When will the updated rates go into effect?
We expect the PSC to complete its review of our filing later this year. If approved, the adjusted rates would go into effect January 1, 2026.

Will my rates go up again the following year?
Yes, as our filing includes a two-step adjustment to electric and natural gas base rates for 2026 and 2027 to ensure customers are only paying for costs incurred in those years.

How can customers reduce their electric and natural gas bills?
There are several ways you can reduce their energy use, which ultimately impacts your bill.

Reduce overall energy consumption. Consider adjusting your thermostat a few degrees, up in the summer or down in the winter, to running appliances in non-peak times.
Energy efficiency improvements. Check out some do-it-yourself, cost-saving tips.
Switch to a rate plan that better matches your energy use patterns, such as our Nights and Weekends or Peak Nights and Weekends programs. Explore rate plan options and use our personalized rate calculator.
Join our Smart Hours program and reduce your energy use while also receiving rewards for participating.

Explore more options in My Account.

What is Alliant Energy doing to manage energy costs?
To manage costs, we continue to operate our system as efficiently as possible. Through prudent, long-term planning, we are investing in a combination of resources including traditional, new and renewable energy sources.

We recently added more than 1 gigawatt of solar generation to the grid making us one of the largest owners and operators of solar generation in Wisconsin. The completion of this project enables us to offset 2026 fuel costs by almost $94 million in 2026, which directly benefits customers.

Fuel cost plan and fuel reconciliation process

What is a fuel cost plan?
The Public Service Commission of Wisconsin (PSC) requires utilities to file an annual forecasted fuel cost plan which is reviewed by the PSC and used to establish the utility rates for the following calendar year. The PSC annually reviews actual monitored fuel costs for over- or under-collection and may approve bill credits or adjustments to reconcile differences. In Wisconsin, fuel costs are a pass-through, meaning utilities such as Alliant Energy do not profit.

What is the “Fuel Adjustment” on my bill?
In December 2024, the Public Service Commission of Wisconsin (PSC) approved our 2025 Fuel Cost plan (Docket 6680-ER-104). Effective January 1, 2025, a $0.006269/kilowatt-hour (kWh) fuel adjustment surcharge was added to your bill to reflect updated costs and our previously approved 2022 fuel reconciliation adjustment (Docket 6680-FR-2022).

In March 2025, we filed an application with the PSC to reconcile the under-collection of 2024 actual fuel costs. In our filing, we request a fuel adjustment of $0.002942/kWh be applied to applicable customer bills from October 1 to December 31, 2025. If approved, for the average residential customer, this amounts to approximately $2/month for the final three months of 2025.

Suggested Topics

Biennial rate filing for 2026 and 2027

Key components

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