Commonwealth Edison Stock History

chase_tower_exelon_hqMany people have Exelon Stock which they previously obtained because they were shareholders of Commonwealth Edison, Exelon, or Unicom Stock. They need to find their cost basis and find historical stock price or to calculate their cost or basis in it to calculate their Capital Loss or Gain for income tax purposes.  You can find very little data available on the internet concerning this.  We put together theses charts to help them. We researched the prices carefully, however, use these at your own risk.  

General Info

On this current page we show a summary of important corporate changes such as mergers, stock-splits and  share exchange factors.  You can get a good summary overview of information affecting your cost basis in this stock by reviewing this chart.  Also we provide some older (pre-1970 historical quotes to give some perspective.


We present Month by Month ComEd/Unicom/Exelon Stock Prices from 1980 thru August 2011. In addition we provide Prices at end of month for year referenced.  Stock prices were mostly derived from archived issues of the NY Times, Standard and Poor’s Stock Price Record for the NYSE, Yahoo Finance historical quotes, and  from various Shareholder Services pages available on the internet from surviving companies. We provide additional external sources at the bottom of this page as Helpful Links.

 Cost Basis Ref-Sheet

The ref-sheet shows you the Date and amount of Dividends paid and the price of Commonwealth Edison, Exelon, and Unicom stock and when the dividend was paid.  The ref-sheet also shows you information on mergers stock split and spin-offs.  We built the Ref-Sheet as a handy sheet to assist you when you are trying to find the effect of dividends, mergers and  stock splits on your cost basis calculations.


ComEd Selected Important Corporate Changes

09/17/1907Incorporated thru Merger of Chicago Edison and Commonwealth Electric
08/14/1937Stock Split 3 for 1
09/22/1961Stock Split 2 for 1
2% Stock Dividend
12/03/19631.5% Stock Dividend
11/30/19641% Stock Dividend
09/01/1994Unicom formed as a holding corp. (per 1 share of ComEd received 1 share Unicom)
10/20/2000Merged into Exelon Corp (per 1 share of Unicom received .875 shares of Exelon Corp.
03/12/2012Merged into Exelon Corp (per 1 share of Constellation Energy received 0.93 shares Exelon.

For a visual chart of these, visit Exelon Chart

ComEd Older Year-End Stock Quotes

YearPrice YearPrice
196937 1/2195337
196848 5/8195234 3/8
47195130 1/2
196652 1/8195033 1/2
196553 1/2194930 3/8
196349 1/8194726 1/2
196244 5/8194633 1/2
196178 1/4194533 7/8
196068 3/4194424 7/8
195957 1/4194324 5/8
195839 3/4194221 1/2
195742 1/8194122 1/2
195639 1/8194029 5/8
195541 3/8193931 1/8
195445 1/2193827 3/8
[table “51” not found /]