NiSource Investor Day to be Held July 22; Second Quarter Earnings Release and Conference Call Scheduled for August 3

MERRILLVILLE, Ind., July 14 /PRNewswire-FirstCall/ — NiSource Inc. (NYSE: NI)
will host an Investor Day in New York City on Thursday, July 22, 2010, starting
at 9:00 a.m. EDT (8 a.m. CDT) and concluding at 1:00 p.m. EDT.

NiSource’s senior management, including its business unit chief executive
officers, will discuss the company’s business profile, strategic direction and
growth investment opportunities, as well as other matters of interest to the
financial community.

A live webcast with accompanying presentations will be available on
www.nisource.com. The webcast also will be archived on the NiSource website.

Second Quarter Earnings Conference Call

NiSource will host an analyst conference call at 9 a.m. EDT (8 a.m. CDT) on
Tuesday, August 3, 2010, to review its second quarter 2010 financial results and
to provide a general business update.

NiSource will release its second quarter earnings before U.S. financial markets
open on August 3.

All interested parties may listen to the conference call live on August 3 by
logging onto the NiSource website at www.nisource.com.

A replay of the earnings conference call will be available beginning at noon EDT
on August 3 through August 10. To access the recording, call 1-888-286-8010 and
enter pass code 25893763. For international participants, please dial
1-617-801-6888 and enter the same pass code, 25893763. A recording of the call
also will be archived on the NiSource website.

About NiSource

NiSource Inc. (NYSE: NI), based in Merrillville, Ind., is a Fortune 500 company
engaged in natural gas transmission, storage and distribution, as well as
electric generation, transmission and distribution. NiSource operating companies
deliver energy to 3.8 million customers located within the high-demand energy
corridor stretching from the Gulf Coast through the Midwest to New England.
Information about NiSource and its subsidiaries is available via the Internet at
www.nisource.com. NI-F

SOURCE NiSource Inc.