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Markets & budgeting

What Illinois electric choice changes—and what it does not

Judge a specific agreement by comparable costs and risk, not a claim that competition always saves money or always costs more.

By Illinois Energy Prices · Jaken Energy
Reviewed October 15, 2026 · Educational guidance, not a live quote

The short answer

Choice changes who can sell eligible accounts their supply; regulated delivery and other tariff obligations remain. Results vary by account, product and period.

The decision this guide helps you make

Judge a specific agreement by comparable costs and risk, not a claim that competition always saves money or always costs more.

Evidence to gather before deciding

Use dated official market reports, customer-class information, actual utility charges and written supplier terms.

The detail that is easy to miss

A statewide market average cannot prove the effect on one business. A valid before-and-after comparison needs comparable usage, billing periods and charge inclusions.

Evaluate the actual counterfactual

Decision case · figures, where used, are hypothetical

Compare identical quantities and periods under old and new supply terms, excluding unchanged delivery. A lower bill after switching might reflect weather or shutdown rather than procurement performance.

What would make this decision ready?

Keep cost, contract risk and service experience distinct. State counterfactual assumptions. Modeled savings should not be described as verified outcomes without supporting terms and quantities.

Separate the layers of the bill

Wholesale energy, capacity, grid services, retail contracting and local delivery serve different functions. A news headline about one layer does not establish an equal change in the whole bill. Label each benchmark by date, geography, unit and customer class. State whether a number is observed, forecast or assumed. A supplier offer has a particular delivery window and expiry; an old average should not be substituted for it.

Create a three-case planning range

Choose an expected usage profile and model a lower, central and higher cost assumption. Hold one variable constant when learning its effect, then combine plausible adverse changes to test cash needs. Record which components the current contract fixes and which can change. Scenario ranges are planning inputs rather than probabilities unless a defensible forecasting method supports those probabilities. Revisit the model when the contract or operations change.

Use contract timing instead of market urgency

Work backward from actual renewal and notice provisions. Allow time to assemble data, compare inclusions, resolve authorization and confirm a start date. A quote expiry can be real without proving that all future prices will be higher. Obtain an updated comparable quote rather than accepting unsupported urgency. Evaluate the cost of waiting alongside the risks of signing a poorly understood product.

A budget sensitivity example

Suppose an illustrative business expects 20,000 kWh a month. A 1 cent/kWh change in a fully exposed energy component changes modeled monthly cost by $200 before other charges. At 30,000 kWh, the same price movement means $300. This calculation says nothing about the probability of the price change, and it should not be applied to components already fixed under a contract. It helps quantify exposure without inventing a forecast.

A review worksheet for What Illinois electric choice changes—and what it does not
RecordWhy it mattersHow to verify
Account and scopeKeeps the decision tied to the right service and customer.Use the current utility, meter and customer class; keep account identifiers private.
Period and unitsPrevents comparisons across different months or measures.Write down billing days and whether the amount is kWh, kW, therms or dollars.
Written termsDistinguishes a claim from an obligation.Save the full proposed agreement, tariff or program notice and its date.
Unknowns and exclusionsShows what the estimate cannot establish.List unresolved charges, eligibility and operating assumptions before deciding.

Use a tool without sending your numbers

A calculator is useful for checking an assumption, not for confirming a tariff, incentive or legal interpretation. Enter only nonidentifying figures in the relevant worksheet. If you need a human review, describe the question and utility first; do not paste an account number or confidential document into the inquiry. Keep the model alongside the written terms so an apparently precise output is not mistaken for a complete quote.

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Sources & further checks

Primary references checked for this guide on October 15, 2026. Follow the source for current tariffs, eligibility and program terms; rates here are not live offers.