LITB LightInTheBox Holding Co Ltd

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 December 2019

Commission File Number: 001-35492

LightInTheBox Holding Co., Ltd.

Tower 2, Area D, Diantong Square

No. 7 Jiuxianqiao North Road

Chaoyang District, Beijing 100015

People’s Republic of China

(Address of principal executive offices)

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

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): £

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): £

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934:

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): n/a

TABLE OF CONTENTS

Exhibit 99.1 — LightInTheBox Reports Third Quarter 2019 Financial Results

Exhibit 99.2 — Press Release dated December 10, 2019, LightInTheBox Received Notification of Falling Below Continued Listing Standard Notice from the NYSE

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