Commonwealth Edison Co. (ComEd) Rate Selection Guide
Commonwealth Edison (ComEd) is the largest electric utility in Illinois, serving approximately 4.1 million customers in the Chicago area. Illinois is a deregulated market — ComEd provides delivery service while customers can choose their electricity supplier. ComEd supports Green Button Connect My Data (third-party API), Green Button Download, and EDI.
Commonwealth Edison Co. (ComEd) Rate Schedule Comparison
| Schedule | Type | Rate | Best For |
|---|---|---|---|
| BES (Residential) | Residential Default | See tariff | Most homes, hourly market-based supply |
| BESH (Hourly Pricing) | Residential Real-Time | See tariff | Active price-responsive customers |
| BES-H (Watt-Hour) | Small Commercial | See tariff | Small businesses under 100 kW |
| BES-MD (Medium Demand) | Medium Commercial | See tariff | Commercial 100-400 kW |
| BES-LD (Large Demand) | Large Commercial | See tariff | Large facilities 400-1,000 kW |
| BES-HV (High Voltage) | Industrial | See tariff | Very large industrial 1,000+ kW |
| Rider POGNM | Net Metering | See tariff | Solar customers under 25 kW |
| ARES Fixed Rate | Competitive Supply | See tariff | Price certainty seekers |
| Municipal Aggregation | Group Supply | See tariff | Residents in participating communities |
Market Overview
Illinois fully deregulated its retail electricity market in 2002. ComEd is a delivery-only utility — it owns and maintains the poles, wires, and meters but does not generate electricity. Customers receive electricity supply either from ComEd's default service (priced at hourly wholesale market rates passed through without markup) or from a licensed Alternative Retail Electric Supplier (ARES). Municipal aggregation programs also allow communities to negotiate group supply rates.
Need to pull your actual usage data to compare rates? See the Commonwealth Edison Co. (ComEd) Data Access Guide →
Current Rate Schedules
ComEd bills consist of two components: delivery charges (regulated, set by the Illinois Commerce Commission) and supply charges (competitive market). Delivery charges include a customer charge, distribution facilities charge, and various riders. Supply charges vary based on whether you use ComEd default hourly pricing or a competitive supplier's fixed/variable rate.
Effective: January 1, 2026 · Full Tariff Book →
| Schedule | Type | Applicability | Structure | Rate |
|---|---|---|---|---|
| BES-H (Basic Electric Service — Watt-Hour) | commercial | Small commercial/industrial customers with demand under 100 kW (non-demand metered) | Delivery: customer charge + distribution charge per kWh. Supply: default hourly pricing or ARES fixed rate. No demand component in delivery charges. | — |
| BES-MD (Basic Electric Service — Medium Demand) | commercial | Commercial customers with demand 100-400 kW | Delivery: customer charge + distribution facilities charge per kW + distribution energy charge per kWh. Supply: default hourly pricing or ARES contract. Demand measured as highest 30-minute interval. | — |
| BES-LD (Basic Electric Service — Large Demand) | industrial | Large commercial/industrial customers with demand 400-1,000 kW | Delivery: customer charge + facilities charge per kW + energy delivery charge per kWh + transmission services charge. Supply: default hourly pricing or negotiated ARES contract. | — |
| BES-HV (Basic Electric Service — High Voltage) | industrial | Very large customers with demand exceeding 1,000 kW at primary/high voltage | Delivery: customer charge + facilities charge per kW + energy delivery per kWh. Voltage-level discount for primary or high-voltage service. Supply: typically negotiated bilateral ARES contract or direct PJM market participation. | — |
Rate Recommendations by Use Case
Small Business (<100 kW)
Small commercial establishment on watt-hour metering without demand charges.
Small commercial customers under 100 kW benefit from no demand charge in delivery — costs are purely volumetric. The supply decision (default vs ARES) matters more at this scale because energy charges dominate. Shop carefully: some ARES offer competitive fixed rates for 12-24 months that may beat default hourly pricing during volatile periods.
- Use PlugInIllinois.org to compare current ARES offers against your recent ComEd default supply cost.
- Beware ARES contract renewal terms — many auto-renew at higher rates. Set calendar reminders.
- LED retrofits and smart HVAC are highest-ROI investments since your bill is purely energy-based.
- Municipal aggregation may override your individual choice — check if your municipality has a program.
- Avoid ARES offers with early termination fees unless you are certain about the contract term.
Mid-Size Commercial (100-400 kW)
Medium commercial with demand metering — offices, retail centers, hotels.
At this scale, delivery includes demand charges (facilities charge per kW) that require active management. The supply side should be competitively bid — larger loads attract better ARES rates. Consider engaging an energy broker to solicit multiple ARES bids and negotiate favorable terms. Demand management reduces the regulated delivery charge component.
- Engage an energy broker to solicit 3-5 competitive supply bids — larger loads get better ARES pricing.
- Manage peak demand aggressively — delivery demand charges cannot be avoided through supply shopping.
- Evaluate block-and-index supply contracts that blend fixed and variable pricing for cost/risk balance.
- Consider PJM capacity and transmission cost allocation — these pass-through charges can be significant.
- Install interval data monitoring to understand your load profile and negotiate better supply terms.
Large Industrial (400+ kW)
Large commercial/industrial on BES-LD or BES-HV with sophisticated energy procurement.
Large customers have the most supply options: bilateral ARES contracts, direct PJM market participation through a retail electricity provider, block-and-index structures, and renewable PPAs. Delivery charges include significant demand and capacity components. Voltage-level optimization and power factor management are important for delivery charge reduction.
- Consider direct PJM market participation through a licensed retail provider for maximum supply flexibility.
- Evaluate renewable Power Purchase Agreements (PPAs) — Illinois RPS requirements create robust wind/solar PPA markets.
- Take service at the highest voltage feasible for delivery charge discounts (primary or high voltage).
- Participate in PJM demand response programs for capacity payments — compatible with most ARES supply contracts.
- Install power factor correction to reduce demand measured by ComEd metering.
Historical Rate Trends
ComEd delivery rates are regulated by the Illinois Commerce Commission and have increased moderately to fund grid modernization and smart meter deployment. Supply rates fluctuate with PJM wholesale markets and ARES competition. The passage of the Climate and Equitable Jobs Act (CEJA) in 2021 accelerated clean energy investment costs flowing into delivery rates.
January 1, 2022
Delivery rate increase under formula rate plan reflecting grid modernization (smart meters, distribution automation) and CEJA compliance investments.
+5.2%January 1, 2023
Supply rate spike due to elevated PJM capacity auction prices and natural gas-driven energy costs. Default supply customers saw higher bills despite stable delivery charges.
+8.1%July 1, 2023
Illinois Commerce Commission approved distribution formula rate update. Includes beneficial electrification rider and EV infrastructure investment.
+3.4%June 1, 2024
PJM capacity price increase (Base Residual Auction results) passed through to all customers. Significant impact on supply costs across all customer classes.
+6.5%January 1, 2025
Delivery rate adjustment reflecting continued CEJA compliance, grid resiliency investments, and performance-based ratemaking pilot. Supply costs moderated as gas prices stabilized.
+2.8%Overall trend: ComEd delivery rates increase 3-5% annually under the formula rate plan, driven by grid modernization and clean energy compliance. Supply costs are more volatile — tied to PJM wholesale markets, capacity auctions, and gas prices. Total bills have risen faster than delivery alone due to PJM capacity price increases in 2023-2024.
Next expected change: June 2026 (PJM capacity year changeover)
Cost Optimization Strategies
In a deregulated market, supply procurement strategy is the largest controllable variable. Delivery charges are regulated and unavoidable but can be reduced through demand management and voltage optimization. The combination of smart supply procurement and active demand management yields the highest savings.
Competitive Supply Procurement
For: All customer classes
Shop for electricity supply on PlugInIllinois.org or through an energy broker. For residential, compare ARES fixed rates against ComEd's recent average default rate. For commercial (>100 kW), solicit multiple competitive bids and consider block-and-index or layered procurement strategies to balance cost and risk.
Hourly Pricing Arbitrage
For: Residential and small commercial with flexible loads
Enroll in ComEd Hourly Pricing and actively shift flexible loads to low-price hours. Overnight prices (11 PM - 6 AM) are typically 30-50% below daytime rates. Summer peak hours (2-6 PM) can be 3-5x overnight rates. Smart home automation and EV scheduling maximize savings without lifestyle impact.
Demand Management (Delivery Reduction)
For: Commercial and industrial (BES-MD, BES-LD, BES-HV)
Delivery demand charges (facilities charge per kW) are assessed based on your highest 30-minute interval. These cannot be avoided through supply shopping — they require physical load management. Install demand monitoring, stagger equipment startups, and use automated curtailment to cap peak demand.
Municipal Aggregation
For: Residential and small commercial in participating municipalities
Many communities in ComEd territory have municipal aggregation programs that negotiate group supply rates. These often beat individual ARES offers due to bulk purchasing power. Check if your municipality has an opt-out aggregation program — you may already be enrolled. Compare the aggregation rate to both default and individual ARES offers.
PJM Demand Response Revenue
For: Commercial and industrial with 100+ kW curtailable load
Large customers can earn capacity payments by enrolling in PJM demand response programs through a Curtailment Service Provider (CSP). Commit to reducing load during PJM emergency events (typically 10-20 hours/year) in exchange for annual capacity payments. Compatible with most ARES supply arrangements.
To implement these strategies, you need your 15-minute interval data. Learn how to download Commonwealth Edison Co. (ComEd) interval data →
Deregulated Market Shopping
Illinois retail electricity choice allows all ComEd customers to select their electricity supplier. ComEd continues to deliver electricity regardless of your supply choice — only the supply portion of your bill changes. You can switch suppliers without any service interruption, equipment changes, or notification to ComEd (your new supplier handles the switch).
How to Compare Commonwealth Edison Co. (ComEd) Suppliers
- 01Visit PlugInIllinois.org — the ICC's official supplier comparison tool that lists all licensed ARES offers for your rate class.
- 02Compare the ARES supply rate to your recent ComEd default supply cost (shown on your bill as 'Electricity Supply Services').
- 03Check if your municipality has a Community Choice Aggregation (CCA) program — these group-negotiated rates often beat individual offers.
- 04For commercial customers (>100 kW), engage an energy broker to solicit multiple bids and negotiate contract terms.
- 05Review contract length, early termination fees, and renewal terms carefully before signing with any ARES.
- 06Contact the ARES directly to enroll — they will handle the switch with ComEd. No service interruption occurs.
Contract Terms for Commonwealth Edison Co. (ComEd) Supply Agreements
- Fixed-rate contracts are typically 12-36 months for residential, with longer terms for commercial.
- Variable-rate plans fluctuate monthly and can spike during extreme weather events.
- Block-and-index contracts (commercial) blend a fixed portion with market-indexed pricing.
- Early termination fees vary: $0 for some residential plans, $50-$200 for others. Commercial penalties can be substantial.
- Auto-renewal clauses are common — most contracts revert to a variable rate or higher fixed rate if not actively renewed.
Common Pitfalls When Shopping Commonwealth Edison Co. (ComEd) Rates
- Introductory teaser rates that spike after 1-3 months — read the full contract, not just the advertised rate.
- Variable rate offers that seem low today but track wholesale markets — these can double during polar vortex events.
- Door-to-door and telemarketing ARES solicitations are common and often misleading — always verify on PlugInIllinois.org.
- Some ARES add hidden fees (monthly service charges, green energy adders) not reflected in the advertised per-kWh rate.
- Switching suppliers does NOT change your delivery charges — any salesperson claiming 'lower ComEd bills' is only affecting the supply portion.
- Municipal aggregation enrollment is opt-out — check if you were auto-enrolled and compare that rate to other options.
Frequently Asked Questions
How do I get 15-minute interval data from ComEd for my commercial portfolio?▾
Sign into your ComEd account, navigate to My Usage, then use Green Button Download My Data to export 15-minute or hourly interval data in XML (ESPI) or CSV format. Data is available for up to 24 months. For automated ongoing access, register as a Green Button Connect vendor.
Does ComEd support automated third-party API access?▾
Yes. ComEd supports Green Button Connect My Data, which provides OAuth-based API access for authorized third parties. Register as a vendor through ComEd's Green Button Connect program. Once registered, customers can authorize your application via the ComEd portal, and data flows automatically.
Can I choose my electricity supplier with ComEd?▾
Illinois is fully deregulated for electricity supply. ComEd provides delivery (wires) service at regulated rates. You can shop for a competitive supplier through the Illinois Commerce Commission comparison site (pluginillinois.org) or contract directly with ARES (Alternative Retail Electric Suppliers). Switching is free and doesn't affect reliability.
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