Nicor Gas Commercial Natural Gas Service
Nicor Gas is the natural gas delivery utility for most of northern Illinois outside Chicago. This guide explains how commercial gas service works in Nicor territory, where supplier choice applies, and what a business needs to price gas accurately. For the statewide picture, start with commercial natural gas in Illinois.
Territory
Nicor Gas serves more than 600 communities across the northern third of Illinois, excluding the City of Chicago (served by Peoples Gas) and the North Shore Gas communities in Lake County and the far north suburbs. Suburbs such as Schaumburg, Naperville, Elk Grove Village, Aurora, Joliet, and Rockford are in Nicor territory. A handful of communities straddle a boundary — Buffalo Grove, for example, has both Nicor and North Shore Gas areas — so verify from the bill for any specific address.
Supply vs. delivery
On Nicor utility service, the gas supply (commodity) is passed through as a purchased-gas cost that adjusts over time, with no utility markup on the gas itself. Nicor's delivery charges cover its distribution system, metering, and applicable riders and taxes. A supplier contract prices the supply portion; delivery stays with Nicor under its tariff. As always, do not apply a supply-price difference to the entire bill.
This distinction is where most gas-comparison errors happen. Because the purchased-gas cost passes through at cost on utility service, the case for a supplier rests on the terms and structure of the supply contract, not on any markup being removed from delivery. Delivery charges — the fixed customer charge and the volumetric distribution and rider components — do not move when supply changes, so any claimed difference should be measured against the supply line alone.
How to read a Nicor commercial bill
A Nicor commercial bill reads cleanly in groups: an account and meter block (service address, account number, rate class, meter, billing period); a usage block (therms for the period, often with prior-year comparison); a supply block (the purchased-gas cost or a supplier's supply charge); and a delivery and other block (the customer charge, distribution, riders, and taxes). Sorting the line items into those groups before comparing offers makes it obvious which charges a supplier can affect and which are fixed by tariff. Our guide to reading a commercial natural gas bill walks the same structure line by line.
Commercial supplier choice
Through Nicor's Choices for You program, eligible commercial customers can buy gas supply from a licensed alternative gas supplier while Nicor continues delivery, metering, billing of delivery charges, and emergency response. Choosing a supplier is a supply-economics and contract-terms decision — the same procurement and contract review discipline that applies to electricity applies here. Compare offers on matched terms: the pricing structure (fixed, index, or a combination), the term length and renewal language, how usage bandwidth or swing is handled given seasonal load, any monthly or account fees, and termination provisions. A headline commodity rate says little until those terms are lined up against one another. The Illinois Commerce Commission licenses and lists alternative gas suppliers, which is the authoritative place to confirm a supplier is licensed to operate in Illinois.
What a Nicor commercial quote requires
- A recent Nicor bill and account number.
- The service address (to confirm territory) and rate class.
- At least 12 months of therm usage — gas load is seasonal, so a full year matters.
- The current supply contract's end date, if on a supplier.
Confirm the territory from the bill
Because some communities straddle a utility boundary, the safest confirmation of who serves a given address is the utility name printed on a recent bill. Nicor covers most of northern Illinois outside Chicago, but the North Shore Gas footprint in Lake County and the far north suburbs and the Peoples Gas territory in the City of Chicago are separate. The bill also fixes the rate class and account number that any accurate quote depends on. For the statewide picture, see commercial natural gas in Illinois.
Sources
- Nicor Gas — Our Service Area (Where We Are)
- Nicor Gas — Choices for You (supplier choice)
- Illinois Commerce Commission — Natural Gas Utility authority
Time-sensitive rate and program details should be confirmed against Nicor's current pages and a recent bill.
Frequently Asked Questions
QDoes Nicor Gas set the price of the gas itself?
On utility service, Nicor passes through the cost of gas it buys (a periodically adjusted purchased-gas cost) with no markup on the commodity, plus its regulated delivery charges. Eligible commercial customers can instead contract the supply portion with a licensed alternative gas supplier through Nicor's Choices for You program, while Nicor continues delivery.
QWhat does Nicor Gas still handle if a business chooses a supplier?
Nicor continues to own and maintain the pipes and meter, deliver the gas, read the meter, bill delivery charges, and respond to leaks and emergencies. A supplier contract affects only the gas supply portion of the bill.
QWhich communities does Nicor Gas serve?
Nicor Gas serves much of the northern third of Illinois outside the City of Chicago — more than 600 communities. It does not serve Chicago (Peoples Gas) or the North Shore Gas communities in Lake County and the far north suburbs. Because some towns sit on a boundary, confirm the serving utility from a recent bill.
QWhy does gas pricing need a full year of therm usage?
Commercial gas load is strongly seasonal — heating months pull far more therms than summer months. A quote built on a partial year can misstate the annual shape, so a full 12 months of therm history gives a supplier the seasonal profile needed to price the supply portion accurately.
QIs a supplier switch the same as switching who delivers my gas?
No. Delivery always stays with Nicor Gas under its regulated tariff. A Choices for You supplier changes only the supply (commodity) portion of the bill; the pipes, meter, delivery charges, and emergency response do not change.