<SEC-DOCUMENT>0001193125-26-228043-index.html : 20260518
<SEC-HEADER>0001193125-26-228043.hdr.sgml : 20260518
<ACCEPTANCE-DATETIME>20260518091544
ACCESSION NUMBER:		0001193125-26-228043
CONFORMED SUBMISSION TYPE:	424B3
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20260518
DATE AS OF CHANGE:		20260518

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			C3is Inc.
		CENTRAL INDEX KEY:			0001951067
		STANDARD INDUSTRIAL CLASSIFICATION:	DEEP SEA FOREIGN TRANSPORTATION OF FREIGHT [4412]
		ORGANIZATION NAME:           	01 Energy & Transportation
		EIN:				000000000
		STATE OF INCORPORATION:			1T
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		424B3
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-276868
		FILM NUMBER:		26991014

	BUSINESS ADDRESS:	
		STREET 1:		331 KIFISSIAS AVENUE
		STREET 2:		ERITHREA
		CITY:			ATHENS
		STATE:			J3
		ZIP:			14561
		BUSINESS PHONE:		011-30-210-625-0001

	MAIL ADDRESS:	
		STREET 1:		331 KIFISSIAS AVENUE
		STREET 2:		ERITHREA
		CITY:			ATHENS
		STATE:			J3
		ZIP:			14561
</SEC-HEADER>
<DOCUMENT>
<TYPE>424B3
<SEQUENCE>1
<FILENAME>d71100d424b3.htm
<DESCRIPTION>424B3
<TEXT>
Document 1 - file: d71100d424b3.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>2
<FILENAME>g71100dsp5_711.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 2 - file: g71100dsp5_711.jpg

</DOCUMENT>
</SEC-DOCUMENT>