Telecom Service One : Profit Warning

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited (the "Stock Exchange") take no responsibility for the contents of this announcement, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

Telecom Service One Holdings Limited 電訊首科控股有限公司

(Incorporated in the Cayman Islands with limited liability)

(Stock Code: 3997)

PROFIT WARNING

This announcement is made by Telecom Service One Holdings Limited (the "Company", together with its subsidiaries, the "Group") pursuant to Rule 13.09 of the Rules Governing the Listing of Securities on the Stock Exchange (the "Listing Rules") and the Inside Information Provisions (as defined under the Listing Rules) under Part XIVA of the Securities and Futures Ordinance (Chapter 571 of the Laws of Hong Kong).

The board of directors (the "Board") of the Company wishes to inform the shareholders of the Company (the "Shareholders") and potential investors that, based on the financial information currently available, the Group anticipates to report a significant decrease in its consolidated net profit for the six months ending 30 September 2018 (the "Period"). The significant decrease in consolidated net profit of the Group for the Period was mainly attributable to, among other factors:

• (i) decrease in revenue of around 30% as compared to the corresponding period of last year. The decrease was mainly due to uncontrollable and unpredictable decrease of repair jobs; and

• (ii) estimated unrealised exchange loss on an approximately RMB27 million fixed deposit.

As the Company is still in the process of finalising the unaudited consolidated interim results of the Group for the Period, the information contained in this announcement is a preliminary assessment by the Board based on the information currently available and the unaudited consolidated management accounts of the Group, which have not been reviewed by the Company's auditors or the audit committee of the Company. Details of the Group's performance will be disclosed in the interim results announcement of the Group for the Period, which is expected to be published in November 2018.

Shareholders and potential investors are advised to exercise caution when dealing in the shares of the Company.

By Order of the Board

Telecom Service One Holdings Limited

Cheung King Shek

Chairman

Hong Kong, 26 September 2018

As at the date of this announcement, the chairman and non-executive director of the Company is Mr. Cheung King Shek; the chief executive officer and executive director of the Company is Mr. Cheung King Fung Sunny; the non-executive directors of the Company are Mr. Cheung King Shan and Mr. Cheung King Chuen Bobby; and the independent non-executive directors of the Company are Mr. Fong Ping, Ms. Kwok Yuen Man Marisa and Mr. Tso Ka Yi.

The English text of this announcement shall prevail over the Chinese text in case of inconsistencies.