<SEC-DOCUMENT>0001193125-17-367497-index.html : 20171212
<SEC-HEADER>0001193125-17-367497.hdr.sgml : 20171212
<ACCEPTANCE-DATETIME>20171212163204
ACCESSION NUMBER:		0001193125-17-367497
CONFORMED SUBMISSION TYPE:	424B5
PUBLIC DOCUMENT COUNT:		3
FILED AS OF DATE:		20171212
DATE AS OF CHANGE:		20171212

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNITIL CORP
		CENTRAL INDEX KEY:			0000755001
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC & OTHER SERVICES COMBINED [4931]
		IRS NUMBER:				020381573
		STATE OF INCORPORATION:			NH
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		424B5
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-221333
		FILM NUMBER:		171252137

	BUSINESS ADDRESS:	
		STREET 1:		6 LIBERTY LANE WEST
		CITY:			HAMPTON
		STATE:			NH
		ZIP:			03842
		BUSINESS PHONE:		6037736504

	MAIL ADDRESS:	
		STREET 1:		6 LIBERTY LANE WEST
		CITY:			HAMPTON
		STATE:			NH
		ZIP:			03842
</SEC-HEADER>
<DOCUMENT>
<TYPE>424B5
<SEQUENCE>1
<FILENAME>d502444d424b5.htm
<DESCRIPTION>424B5
<TEXT>
Document 1 - file: d502444d424b5.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>2
<FILENAME>g502444g58e87.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 2 - file: g502444g58e87.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>3
<FILENAME>g502444g87d19.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 3 - file: g502444g87d19.jpg

</DOCUMENT>
</SEC-DOCUMENT>