C3is Inc. (NASDAQ: CISS) to buy $22.9M product tanker and expand fleet

Rhea-AI Filing Summary

C3is Inc. has agreed to acquire a 2011 South Korean-built product tanker with 47,203 deadweight tons of capacity for a purchase price of $22.9 million from an entity affiliated with Brave Maritime Corp Inc. The deal involves related parties connected to the Vafias family and was approved by the Company’s independent directors, who obtained independent vessel valuations and used the average of those valuations to set the price.

The tanker is expected to be delivered between Q1 and Q2 2026, and C3is has the option to pay the purchase price one year after the agreement date without interest. After delivery of this vessel and the previously announced pending product tanker, the Company expects to operate a fleet of six vessels with a total capacity of 310,667 deadweight tons, including three Handysize drybulk carriers, one Aframax oil tanker and two product tankers.

Insights

Maritime equity analyst

C3is adds a $22.9M product tanker, expanding its fleet mix.

C3is Inc. is growing its fleet with a 2011 South Korean-built product tanker purchased for $22.9 million. The vessel adds 47,203 deadweight tons of capacity and will operate alongside the company’s existing Handysize drybulk carriers and Aframax oil tanker, increasing exposure to product tanker trades once delivered between Q1 and Q2 2026.

The seller is affiliated with Brave Maritime and the Vafias family, so governance controls are important. The transaction was approved by independent directors, who relied on third-party valuations and used the average price, which may help align the deal with market levels. The option to defer payment for one year after the purchase agreement date without interest provides financing flexibility, though the filing does not detail how this interacts with the company’s broader capital structure.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of January 2026

Commission File Number 001-41717

C3IS INC.

(Translation of registrant’s name into English)

331 Kifissias, Avenue Kifissia 14561 Athens, Greece

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒   Form  40-F ☐

INFORMATION CONTAINED IN THIS FORM 6-K REPORT

Vessel Acquisition Agreement

C3is Inc. (the “Company”) has entered into an agreement to acquire a 2011 South Korean-built product tanker with 47,203 deadweight tons (dwt) capacity for a purchase price of $22.9 million, from an entity affiliated with Brave Maritime Corp Inc. The transaction with Brave Maritime, which is affiliated with members of the Vafias family, was approved by the independent directors of the Company, which obtained independent valuations of the vessel, and used the average price of these valuations.

The vessel is expected to be delivered between Q1 and Q2 2026. The Company has the option to pay for the vessel one year after the date of the purchase agreement, without interest.

Following this vessel delivery, and assuming no further acquisitions or dispositions other than the pending product tanker acquisition previously announced, the Company’s fleet will total 6 vessels, three Handysize drybulk carriers with a total capacity of 97,664 dwt, an Aframax oil tanker with a capacity of approximately 115,800 dwt and two product tankers with a capacity of approximately 97,203 dwt, resulting in a fleet total capacity of 310,667 dwt.

*****

This report on Form 6-K is hereby incorporated by reference into the Company’s Registration Statement on Form S-8 (Reg. No. 333-273306) filed with the Securities and Exchange Commission on July 18, 2023 and Registration Statement on Form F-3 (Reg. No. 333- 285135) filed with the Securities and Exchange Commission on February 21, 2025.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: January 20, 2026

C3IS INC.
By:		/s/ Nina Pyndiah
Name:		Nina Pyndiah
Title:		Chief Financial Officer

FAQ

What vessel did C3is Inc. (CISS) agree to acquire?

C3is Inc. agreed to acquire a 2011 South Korean-built product tanker with a 47,203 deadweight ton capacity.

How much is C3is Inc. (CISS) paying for the new product tanker?

C3is Inc. agreed to a $22.9 million purchase price for the product tanker.

Who is selling the vessel to C3is Inc. (CISS)?

The vessel is being purchased from an entity affiliated with Brave Maritime Corp Inc., which is affiliated with members of the Vafias family.

How was the related-party vessel transaction approved at C3is Inc. (CISS)?

The deal was approved by independent directors of C3is Inc., who obtained independent valuations of the vessel and used the average of those valuations to set the price.

When will the newly acquired tanker be delivered to C3is Inc. (CISS)?

The tanker is expected to be delivered between Q1 and Q2 2026.

What payment flexibility does C3is Inc. (CISS) have for the vessel acquisition?

C3is Inc. has the option to pay for the vessel one year after the date of the purchase agreement, without interest.

What will C3is Inc.’s (CISS) fleet look like after the tanker delivery?

Assuming no further acquisitions or dispositions besides the pending product tanker, C3is Inc. expects a fleet of 6 vessels with 310,667 deadweight tons of total capacity: three Handysize drybulk carriers, one Aframax oil tanker and two product tankers.