NorthWestern Energy Rate Selection Guide
NorthWestern Energy is an investor-owned electric and natural gas utility serving roughly 850,000 customers across Montana, South Dakota, and Nebraska. Customers access billing and usage data through the My Energy Account portal and Detailed Energy Usage tool, while large C&I accounts can establish EDI feeds through the Key Account program. The utility is mid-rollout of two-way AMI smart meters across Montana.
NorthWestern Energy Rate Schedule Comparison
| Schedule | Type | Rate | Best For |
|---|---|---|---|
| GSEDS-1 | Commercial | Service charge + per-kWh energy + demand (see tariff) | Small to mid-size commercial sites |
| GSEDS-2 | Commercial | Service charge + energy + per-kW demand (see tariff) | Larger demand-metered commercial loads |
| Large Industrial (over 1 MW) | Industrial | Demand-metered, contract terms may apply | Industrial / manufacturing over 1 MW |
| ISEDS-1 | Agricultural | Seasonal energy + demand (see tariff) | Irrigation pumping |
Market Overview
Montana is a fully regulated, vertically integrated market. NorthWestern Energy provides bundled generation, transmission, distribution, and supply, with rates approved by the Montana Public Service Commission. Standard commercial and industrial customers cannot shop for a competitive electricity supplier.
Need to pull your actual usage data to compare rates? See the NorthWestern Energy Data Access Guide →
Current Rate Schedules
NorthWestern Energy's Montana electric and gas rates are set by the Montana PSC and recovered through base rates plus the Power Costs and Credit Adjustment Mechanism (PCCAM) for electric supply. As of late 2025, the residential electric all-in rate verified on the MT PSC rate summary was approximately $0.143/kWh, and the residential gas total rate was roughly $0.75/therm. Commercial and industrial customers take service under General Service (GSEDS) demand-metered schedules that combine a monthly service charge, a per-kWh energy charge, and a per-kW demand charge; exact C&I cents-per-kWh and per-kW figures are published in the GSEDS-1 and GSEDS-2 tariff sheets in the Montana tariff book and are not reproduced here. Following the November 2025 rate case order, base electric rates increased materially effective February 1, 2026.
Effective: February 1, 2026 · Full Tariff Book →
| Schedule | Type | Applicability | Structure | Rate |
|---|---|---|---|---|
| GSEDS-1 General Service Electric Delivery Service | commercial | Small to mid-size commercial customers (non-demand and small-demand general service). | Monthly service charge plus per-kWh energy charge; demand charge applies above stated thresholds. Energy supply recovered via PCCAM. | See GSEDS-1 tariff sheet for current cents/kWh (not independently verified)+ Per-kW demand charge for qualifying accounts; see GSEDS-1 tariff |
| GSEDS-2 General Service Electric Delivery Service | commercial | Larger general service / demand-metered commercial customers. | Monthly service charge, per-kWh energy charge, and per-kW demand charge; supply via PCCAM. | See GSEDS-2 tariff sheet (not independently verified)+ Per-kW demand charge; see GSEDS-2 tariff |
| Large Industrial (over 1 MW) | industrial | Industrial customers over 1 MW demand; eligible for Key Account services and EDI. | Demand-metered service with energy and demand charges; large-customer contract terms may apply. Refer to the Montana electric tariff book. | Structure described qualitatively; see tariff book+ Per-kW demand charge (primary driver of large C&I bills) |
| ISEDS-1 Irrigation Service Electric Delivery Service | agricultural | Agricultural irrigation pumping loads. | Seasonal energy and demand-based charges for irrigation; see ISEDS-1 tariff. | See ISEDS-1 tariff sheet+ Demand charge per ISEDS-1 tariff |
| Natural Gas General Service (Commercial) | commercial | Commercial natural gas customers in Montana. | Monthly service charge plus per-ccf/therm delivery and gas supply charges. Residential gas total rate was roughly $0.75/therm in late 2025 per MT PSC; commercial schedules differ. | See Montana natural gas tariff book+ N/A (gas) |
Rate Recommendations by Use Case
Mid-size commercial building
Commercial offices and retail under demand metering should track peak usage to manage demand charges.
GSEDS schedules combine energy and demand charges; reducing coincident peak directly lowers the demand component.
- Pull hourly data from the Detailed Energy Usage tool
- Stagger HVAC and equipment start-up to flatten peaks
- Confirm whether your meter is AMI for interval visibility
Large industrial / manufacturing (over 1 MW)
Large plants should establish Key Account EDI feeds and focus on demand management.
Demand charges dominate large C&I bills; automated EDI data enables continuous monitoring and demand reduction.
- Contact a Key Account Manager for EDI (888-467-2669)
- Request transaction sets 867 and 820 for detailed billing
- Use interval data to target peak-shaving
Multi-site portfolio / property manager
Portfolios should consolidate data via the Continuous Service Agreement portal or aggregator feeds.
Centralized 24-month history per site enables benchmarking and retrofit prioritization across properties.
- Enroll in the Continuous Service Agreement portal
- Benchmark usage per square foot or per unit
- Use Nectar for automated billing and interval data feeds — docs.nectarclimate.com
Agricultural irrigation operation
Irrigation customers should align pumping with off-peak periods under ISEDS-1.
Seasonal irrigation loads can be scheduled to reduce demand-related costs.
- Review ISEDS-1 seasonal terms
- Schedule pumping outside peak demand windows
- Track interval usage where AMI is available
Historical Rate Trends
NorthWestern Energy's Montana electric rates have risen steadily, driven by supply costs recovered through the PCCAM and by base-rate cases. The 2024/25 electric general rate case concluded with a Montana PSC order in November 2025.
February 1, 2026
Base electric rates increased following the MT PSC's November 2025 rate case order; the Commission approved roughly $246M of additional rate base (a reduction of about $43M from NorthWestern's request). The decision raised residential base electric rates about 17%, equating to roughly a 12% overall residential bill increase vs. July 2024; C&I demand-metered schedules also adjusted.
+17% base (residential)June 1, 2025
Seasonal/PCCAM supply movement raised the residential all-in electric rate to roughly $0.152/kWh in summer 2025 (per MT PSC rate summary).
Seasonal supply increaseOverall trend: Upward. The MT PSC rate summary shows the residential all-in electric rate climbing from roughly $0.122/kWh in late 2024 to about $0.143/kWh by late 2025, before the February 2026 base-rate increase took effect.
Next expected change: Future PCCAM supply true-ups (typically annual) and any subsequent base-rate filing with the MT PSC.
Cost Optimization Strategies
Because NorthWestern's C&I bills are demand-driven, the highest-leverage savings for commercial and industrial customers come from reducing peak demand and improving load factor, using interval data from the Detailed Energy Usage tool.
Peak demand reduction
For: Demand-metered C&I (GSEDS-2, over 1 MW)
Use hourly interval data to identify and stagger peak loads, lowering the per-kW demand charge that drives GSEDS and large-industrial bills.
Load factor improvement
For: All demand-metered C&I
Flatten consumption across the billing period to raise load factor and reduce the ratio of demand charges to energy used.
Key Account EDI + analytics
For: C&I over 1 MW
Establish automated EDI feeds to feed energy-management software for continuous bill auditing and anomaly detection.
Net metering for on-site solar
For: C&I with suitable rooftop/site
AMI smart meters support net metering; on-site generation can offset energy charges where economical.
To implement these strategies, you need your 15-minute interval data. Learn how to download NorthWestern Energy interval data →
Frequently Asked Questions
How can a commercial customer download interval usage data from NorthWestern Energy?▾
Log in to My Energy Account, go to Billing then View Detailed Usage, select Hour/Day/Week/Month granularity and a date range, then click the blue Download button to export CSV/Excel. Hourly data is available where AMI smart meters are deployed; legacy AMR meters provide monthly data only.
Does NorthWestern Energy support Green Button or a public API for C&I data?▾
No. NorthWestern does not offer Green Button Download My Data or Connect My Data and has no documented public developer API. Large C&I customers instead use the Key Account EDI program (ANSI X12) for automated billing and usage feeds, or may access data through Nectar's API — see docs.nectarclimate.com.
How does a third party (consultant or aggregator) get authorized access to a customer's data?▾
For accounts over 1 MW, the customer provides written authorization and the third party contacts a Key Account Manager to establish EDI trading-partner status via VAN or direct SFTP. For smaller accounts, customers may share portal login credentials or designate the third party through a property-manager portal.
Can commercial and industrial customers in Montana choose a competitive electricity supplier?▾
No. Montana is a regulated, vertically integrated market for standard C&I customers. NorthWestern Energy provides bundled generation and delivery with rates set by the Montana PSC; there is no competitive retail supplier shopping for typical commercial accounts.
What drives commercial and industrial electricity costs at NorthWestern Energy?▾
C&I bills under the GSEDS demand-metered schedules combine a fixed monthly service charge, a per-kWh energy charge (with supply recovered via the PCCAM), and a per-kW demand charge. The demand charge often dominates larger bills, so peak demand reduction and load-factor improvement are the highest-leverage cost levers.
Automate NorthWestern Energy Rate Analysis with Nectar
Nectar continuously monitors your NorthWestern Energy rate options and alerts you when a better schedule is available. Save 10-30% on energy costs.
Nectar for Energy & Sustainability Teams
Managing utility costs for commercial or industrial buildings? Nectar offers a free rate analysis — we'll review your current rate schedules and identify where switching tariffs or shifting load can save 10-30%.
Get a Free Rate AnalysisNectar for Energy Brokers & Consultants
Advising clients on rate optimization? Nectar works with energy consultants who need reliable interval data and automated rate comparison tools.
Partner with Us