Utility overview
- Legal name
- NorthWestern Energy Public Service Corporation d/b/a NorthWestern Energy
- Parent organization
- Not listed
- Ownership type
- Investor-Owned
- Utility class
- Major Regulated
Back to South Dakota — SD utilities
NorthWestern Energy Public Service Corporation d/b/a NorthWestern Energy
Investor-Owned · Major Regulated
Official website and contact
- Official website: Visit official website (opens in a new tab)
- Customer service: 1-888-467-2669
- Gas emergency: Not listed
- Email: Not listed
- Address: Not listed
Published state services
South Dakota — SD
Service area: Natural gas distribution in South Dakota (~49,800 gas customers per SDPUC NG24-005 stipulation).
Rate jurisdiction: South Dakota Public Utilities Commission
Customer classes: Commercial, Residential
Last confirmed: Aug 27, 2026
- State customer URL: Open link (opens in a new tab)
- Tariff or territory source: Open link (opens in a new tab)
Utility identity sources
- NorthWestern Energy — South Dakota Gas Rate Schedule (opens in a new tab)
Tariff · NorthWestern Energy
- NorthWestern Energy home (opens in a new tab)
Official Utility Website · NorthWestern Energy
State-service sources
South Dakota — SD
- SD PUC — NG24-005 Settlement Stipulation (NorthWestern Energy) (opens in a new tab)
State Regulator Inventory · SD PUC
Verified utility identity
Verified means GCC confirmed utility identity, retail gas-distribution status, and state-service evidence against authoritative sources.
Confirmation status
- Last confirmed
- Aug 27, 2026
- Reconfirmation status
- Current
Directory-information notice
GCC provides directory information only. Listings are not legal advice, regulatory advice, endorsements, or guarantees of utility service eligibility.
Service-area summaries are high-level and do not guarantee service at a specific address. Contact the listed utility directly for address-level eligibility.