FORM 5 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). Form 3 Holdings Reported Form 4 Transactions Reported

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL OMB Number: 3235-0362 Expires: January 31, 2005 Estimated average burden hours per response... 1.0

1. Name and Address of Reporting Person * COLLIN MARK H 2. Issuer Name and Ticker or Trading Symbol UNITIL CORP [UTL] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) SR. VP , CFO & Treasurer (Last) (First) (Middle) 6 LIBERTY LANE WEST 3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year) 12/31/2010 (Street) HAMPTON, NH 03842 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Reporting (check applicable line) _X_ Form Filed by One Reporting Person ___ Form Filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned at end of Issuer's Fiscal Year (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Amount (A) or (D) Price Common stock, no par value 02/16/2010   J(1) 197.468 A $ 21.186 0 D   Common stock, no par value 05/14/2010   J(2) 214.569 A $ 21.921 0 D   Common stock, no par value 08/16/2010   J(3) 224.117 A $ 21.317 0 D   Common stock, no par value 11/15/2010   J(4) 217.315 A $ 22.341 0 D   Common stock, no par value 02/07/2011   J(5) 450 A $ 22.31 0 D   Common stock, no par value 02/07/2011   J(6) 328 A $ 22.31 14,289.849 D   Common stock, no par value 12/31/2010   J(7) 268.409 A $ 22.07 2,294.21 I Held in trust (8)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

SEC 2270 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned at End of Issuer's Fiscal Year (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
COLLIN MARK H 6 LIBERTY LANE WEST HAMPTON, NH 03842	Â	Â	  SR. VP , CFO & Treasurer	Â

Signatures

/s/ Mark H. Collin		02/08/2011
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Acquisition pursuant to reinvestment of dividends.
(2)	Acquisition pursuant to reinvestment of dividends.
(3)	Acquisition pursuant to reinvestment of dividends.
(4)	Acquisition pursuant to reinvestment of dividends.
(5)	Shares granted pursuant to the Unitil Corporation Restricted Stock Plan on February 6, 2008. Shares represent 25% of total grant and vested on February 7, 2011. The terms of the Unitil Corporation Restricted Stock Plan specify valuation at time of vesting. Vested shares are unrestricted and fully transferable by owner.
(6)	Shares granted pursuant to the Unitil Corporation Restricted Stock Plan on February 5, 2010. Shares represent 25% of total grant and vested on February 7, 2011. The terms of the Unitil Corporation Restricted Stock Plan specify valuation at time of vesting. Vested shares are unrestricted and fully transferable by owner.
(7)	Shares were purchased between January 1 - December 31, 2010 at an average price of $22.07 under the terms and conditions of the Unitil Corporation Tax Deferred Savings and Investment Plan.
(8)	Shares are held in trust under the terms of the Unitil Corporation Tax Deferred Savings and Investment Plan.

Note: File three copies of this Form, one of which must be manually signed. If space provided is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.