Nov 2 (Reuters) - Exelon Corp reported third-quarter revenue that beat Wall Street expectations on Thursday, boosted by strong results in its units that serve customers in Illinois and Pennsylvania.

The company said utility earnings in the quarter were driven primarily by rate increases at its local energy companies, which helped offset the impact of higher costs, including those incurred due to storms.

Exelon is composed of BGE, ComEd, PECO, Atlantic City Electric, Delmarva Power and Pepco and a shared corporate services unit, Exelon Business Services Co.

ComEd, which is headquartered in Chicago with more than 4 million customers across the northern Illinois region, saw its quarterly adjusted earnings increase to $338 million, from $293 million in the year-ago period.

Exelon's total revenue stood at $5.9 billion, above analysts' average estimate of $5.05 billion, as per LSEG data.

On an adjusted basis, the company reported a profit of 67 cents per share, in line with analysts' average estimate.

The company narrowed its full-year profit forecast to $2.32-$2.40 per share, from $2.30-$2.42 per share. (Reporting by Mrinalika Roy in Bengaluru; Editing by Savio D'Souza)