The following companies are the major competitors of WGL Holdings, Inc.

• Nicor Inc.
• Allegheny Energy, Inc.
• National Fuel Gas Company
• KeySpan Corporation
• Pepco Holdings
• Atmos Energy Corporation
• AmeriGas Partners, L.P.
• AGL Resources Inc.
• Piedmont Natural Gas Company, Inc.
• UniSource Energy Corporation
• New Jersey Resources Corporation
• Northwest Natural Gas Company
• EnergySouth, Inc