Gas Utilities Directory — utility profile
Columbia Gas of Maryland
Maryland · Investor-Owned · Major Regulated
Utility overview
- Utility name
- Columbia Gas of Maryland
- Legal name
- Columbia Gas of Maryland, Inc.
- Parent organization
- NiSource
- Ownership type
- Investor-Owned
- Utility class
- Major Regulated
- Rate jurisdiction
- Maryland Public Service Commission
- State directory
- Maryland utilities
- Customer classes
- Commercial, Residential
Official website and contact
- Official website
- www.columbiagasmd.com
- Customer service phone
- 888-460-4332
- Not published
Contact details are shown only where the utility publishes them.
Published state services
Maryland
Western Maryland counties of Washington, Allegany, and Garrett (Maryland OPC).
Customer classes: Commercial, Residential
Last confirmed: August 22, 2026
State customer informationVerification sources
- Columbia Gas of Maryland Natural Gas Tariff
Columbia Gas of Maryland, Inc. · Tariff — Rate RS – Residential Service; Commercial Customer definition; PSC of Maryland. (accessed 2026-08-22)
- Columbia Gas
Maryland OPC · State Regulator Inventory — ~34,000 customers; Washington, Allegany, Garrett. (accessed 2026-08-22)
- Gas Commodity Fact Sheet July 2026
Maryland PSC · State Regulator Inventory — Names Columbia Gas of Md. as a major MD gas utility. (accessed 2026-08-22)