Northern Indiana Public Service Company's (NIPSCO's) natural gas service territory covers 32 counties.
To compare average natural gas bills, see the IURC's monthly residential surveys.
Key components in a natural gas bill include:
- Gas costs
- Base rates
- Trackers
- Quarterly Gas Cost Adjustments
NIPSCO’s GCA rate adjustments are approved every three months under IURC Cause Number 43629. Orders approving rate adjustments include specific bill impacts and are available from the electronic files on the IURC website.
To search:
- Go to https://iurc.portal.in.gov/
- Click the “Start” button under “Search for a Docketed Case”
- Enter the Cause Number noted above
- The most recent GCA case will appear first
- Base Rates
Base rates cover "non-gas" costs for a utility, including operational, maintenance, and capital costs. A natural gas utility is allowed to earn a return on this portion of the bill.
NIPSCO's current base rates were established in a July 31, 2024 IURC order.
The order approved an increase of $120.9 million, a $41 million reduction from the utility's initial request. The OUCC filed testimony supporting the agreement on Mar. 25, 2024. All formal parties to the case either signed the agreement or agreed to not oppose it.
All publicly filed documents in this case (Cause No. 45967) are available on the IURC's website.
NIPSCO's previous gas base rates were approved in 2022.
- Trackers
State law allows natural gas and electric utilities to seek IURC approval of 5-to-7-year plans for infrastructure improvements.
- If a plan is approved, the utility may then seek incremental rate increases as the projects proceed.
- Most costs are recovered through the Transmission, Distribution, and Storage System Improvement Charge (TDSIC). TDSIC tracker cases occur every 6 months.
- NIPSCO's current gas TDSIC plan received Commission approval in July 2020.
NIPSCO and other gas utilities may also recover federally required pipeline safety costs through a rate tracker.
NIPSCO's most recent Federally Mandated Cost Adjustment was approved in December 2021. In Cause No. 45703, NIPSCO received Commission approval of a 5-year plan for pipeline safety compliance.
In a pending case (Cause No. 46222), NIPSCO is seeking approval of a new 3-year plan. The OUCC is reviewing the $244 million request and is scheduled to file testimony on July 15, 2025.
Pending Case: NIPSCO Gas TDSIC Plan
NIPSCO's gas utility has filed a new Transmission, Distribution, and Storage System Improvement Charge (TDSIC) case under Cause No. 46342.
The Indiana General Assembly enacted the Transmission, Distribution, and Storage System Improvement Charge (TDSIC) statute in 2013 and updated it in 2019.
Under the statute, a utility may file a five-to-seven year TDSIC plan with the Commission. If the plan is approved, the utility can then recover 80 percent of the costs as they are incurred through TDSIC tracker filings as often as every six months. The remaining 20 percent are deferred until the utility’s next base rate case, which must be filed before the end of the plan’s term.
NIPSCO's initial filing requested recovering approximately $765 million in proposed projects. After a discovery made by the OUCC, NIPSCO's request was revised for approximately $741 million in recovery over a five year period.
Their proposal seeks to increase capacity for gas delivery to Stueben and Lagrange Counties, replace aging gas lines, and various other projects to monitor and improve gas lines.
The OUCC is reviewing the request and will file testimony by March 11, 2026.
The OUCC is inviting comments on the case through March 4. Comments can be submitted here.
2-19-2026
