EXHIBIT 11.

UNITIL CORPORATION AND SUBSIDIARY COMPANIES

COMPUTATION OF EARNINGS PER AVERAGE COMMON SHARE
OUTSTANDING

(000s except for per share data)

(UNAUDITED)





|                                                               |  |                                 |           |                                |   |           |  |      |           |  |   |          
|-------------------------------------------------------------- |  | ------------------------------- | --------- | ------------------------------ | - | --------- |  | ---- | --------- |  | - | ---------
|                                                               |  | Three Months EndedSeptember 30, |           | Nine Months EndedSeptember 30,
|(000s, except per share data)                                 |  | 2006                            |           | 2005                           |   | 2006      |  | 2005
|Net Income                                                     |  | $                               | 1,827     |                                | $ | 1,601     |  | $    | 5,305     |  | $ | 5,847    
|Less: Dividend Requirements on Preferred Stock                 |  |                                 | 35        |                                |   | 39        |  |      | 99        |  |   | 117      
|                                                               |  |                                 |           |                                |   |           |  |      |           |  |   |          
|Net Income Applicable to Common Stock                          |  | $                               | 1,792     |                                | $ | 1,562     |  | $    | 5,206     |  | $ | 5,730    
|                                                               |  |                                 |           |                                |   |           |  |      |           |  |   |          
|Weighted Average Number of Common Shares Outstanding  Basic   |  |                                 | 5,605,208 |                                |   | 5,558,238 |  |      | 5,591,692 |  |   | 5,546,194
|                                                               |  |                                 |           |                               
|Dilutive Effect of Stock Options and Restricted Stock          |  |                                 | 13,874    |                                |   | 18,813    |  |      | 14,073    |  |   | 16,920   
|                                                               |  |                                 |           |                               
|Weighted Average Number of Common Shares Outstanding  Diluted |  |                                 | 5,619,082 |                                |   | 5,577,051 |  |      | 5,605,765 |  |   | 5,563,114
|                                                               |  |                                 |           |                               
|Earnings Per Share  Basic                                     |  | $                               | 0.32      |                                | $ | 0.28      |  | $    | 0.93      |  | $ | 1.03     
|                                                               |  |                                 |           |                               
|Earnings Per Share  Diluted                                   |  | $                               | 0.32      |                                | $ | 0.28      |  | $    | 0.93      |  | $ | 1.03