Serving court documents across the Hong Kong–Chinese Mainland boundary is a common procedural hurdle in civil proceedings. From 30 March 2027, a new mutual-service arrangement will replace the current framework that has operated for over 27 years, introducing additional ways to progress cross-boundary disputes. The new Arrangement on Mutual Service of Judicial Documents in Civil and Commercial Proceedings between the Chinese Mainland and the Hong Kong Special Administrative Region (New Arrangement)11 was signed on 20 April 2026 by the Supreme People’s Court and the Hong Kong SAR government To implement the New Arrangement, three pieces of subsidiary legislation were made on 12 October 2026 and gazetted on 16 October 2026: Rules of the High Court (Amendment) (No. 2) Rules 202622 Rules of the District Court (Amendment) (No. 2) Rules 202633 Matrimonial Causes (Amendment) Rules 202644 Need for enhanced mechanism Under Article 95 of the Basic Law, the Hong Kong SAR may, through consultations and in accordance with law, maintain juridical relations with the judicial organs of other parts of the country, and they may render assistance to each other. The original arrangement for Mutual Service of Judicial Documents in Civil and Commercial Proceedings between the Chinese Mainland and Hong Kong courts (Existing Arrangement)55 was concluded between Hong Kong and the Chinese Mainland in January 1999. Over the past 27 years since the Existing Arrangement was implemented, the volume of cross boundary service requests has surged, but parties have encountered persistent practical obstacles in effecting successful service. Common reasons for failure to effect service include problems with the recipient’s address and unknown whereabouts66. Over the years, many legal practitioners have had the unpleasant experience of spending months waiting for service to be effected, only to receive a notification saying service was unsuccessful because the recipient was not found at the given address, or no one answered the door. Yet there was no clear answer as to what the plaintiff could do to make another attempt. In cases where the plaintiff later discovered additional addresses or just requested the authority to make another attempt at the same address, the process would drag on for another lengthy period, only for the plaintiff to find itself back to where it was a few months ago, and by then the validity of the writ had probably expired. It is therefore natural for the Legislature of Hong Kong to observe that, where service cannot be effected through the Existing Arrangement, parties often cannot proceed with their cases and their legitimate rights and interests are affected . Against this context, the New Arrangement was introduced to add options and clearer operational features so that cross boundary disputes can move forward more predictably. How the new framework will operate The amendments to the Rules of the High Court (RHC) and Rules of the District Court (RDC) introduce the New Arrangement into Order 11, which governs service outside Hong Kong. The revised rule 5A identifies the permitted service routes, while the new rules 5B-5F prescribe their operation. The new rule 5G contains supplementary provisions, including provisions dealing with cases where the prescribed evidence of receipt is unavailable, translation requirements and the applicable date of service where more than one method is used. Significantly, the amendments move away from reliance on court-to-court entrustment as the principal mechanism for service in the Chinese Mainland and introduce a broader range of service channels. Service through the judicial authorities remains available, but parties will also be able to effect service by post, electronic means or through designated bodies such as law firms. In appropriate circumstances, service by public announcement is also available as a court-directed alternative. The reform also extends to matrimonial proceedings. Under the amended rule 109 of the Matrimonial Causes Rules, any document in matrimonial proceedings may be served outside Hong Kong in accordance with Order 11, rules 5, 5A and 6 of the RHC, as if the document were a writ. The additional modes of service available for service in the Chinese Mainland therefore apply equally in the matrimonial context. Five methods for service in the Chinese Mainland under the New Arrangement Under the amended Order 11, a writ in civil proceedings may be served on a person in the Chinese Mainland by one or more of five prescribed methods. Different methods may be effected in parallel. 1. Service through Chinese Mainland judicial authorities The new rule 5B retains the court-to-court service mechanism. The plaintiff must lodge a request in the registry, together with the prescribed sealed copies of the writ, any required sealed order granting leave to serve out of the jurisdiction, and a suitably modified Form 14 for acknowledgement of service. The request must identify the recipient and address, describe the proceedings and indicate any preferred method of service. The registrar will transmit the documents to the relevant Chinese Mainland judicial authorities to effect service. The new rule also expressly permits the registrar to transmit the documents to the relevant Chinese Mainland judicial authorities electronically. A writ transmitted electronically in this manner has the same legal effect as a sealed copy. 2. Service by post The new rule 5C permits the plaintiff to serve the documents by post from Hong Kong. The prescribed package comprises the sealed writ, any required order granting leave to serve out of the jurisdiction, a suitably modified Form 14 for acknowledgement of service, and the new Form 15B for receipt of service. The date of service is ordinarily the date on which the recipient signs the Form 15B or the postal proof of receipt. Where both documents are signed, the signature date on the postal proof prevails. Accordingly, a recipient-signed postal proof may establish service notwithstanding that the Form 15B has not been returned. Where neither signed document is available, the rules provide a separate mechanism under rule 5G, to be discussed below. 3. Service by electronic transmission The new rule 5D provides for electronic service where the recipient has given a non-verbal notice consenting to accept service electronically and designating an electronic address. A recipient who has not given such prior consent may nevertheless be taken to have consented by acknowledging receipt, participating in the proceedings, providing an electronic service address in specified court documents or otherwise submitting to the court’s jurisdiction. The prescribed documents must be transmitted in a manner that enables receipt to be ascertained and complies with the relevant practice directions. Subject to the applicable requirements, the transmission record, together with the absence of a failed-delivery notification, constitutes the prescribed evidence of electronic service unless the contrary is shown. The date of service is deemed to be the seventh day after transmission unless proven to the contrary. 4. Service through designated bodies The new rule 5E introduces a route for personal service through designated bodies in the Chinese Mainland. Under this route, the plaintiff may instruct a Chinese Mainland law firm or notarial institution to deliver the relevant court documents personally to the recipient. The documents must include the new Form 15B for receipt of service, which the recipient is asked to sign upon receipt. Service is ordinarily treated as effected on the date on which the recipient signs Form 15B. 5. Service by public announcement The new rule 5F provides a fallback method where the court is satisfied that service by any of the other four methods is impracticable. The plaintiff may apply for an order permitting service by public announcement, supported by an affidavit setting out the relevant circumstances, as well as a draft of the proposed announcement. Once the order is made, the plaintiff must lodge with the registry a prescribed request identifying the recipient by full name and address and describing the nature of the proceedings, together with any required sealed order granting leave to serve out of the jurisdiction. The registrar will then request the Chinese Mainland judicial authorities to arrange for the public announcement. Service is deemed to have been effected on the 60th day after the announcement. Provisions for unavailable proof of receipt The new rule 5G contains supplementary provisions governing service under the new framework. Importantly, it addresses circumstances in which the prescribed proof of receipt is unavailable. Where the required receipt does not exist, the rules allow the court to consider other evidence relevant to whether and when the writ came to the recipient’s knowledge. The absence of the prescribed receipt does not therefore necessarily mean that service cannot be established. Rule 5G also addresses the date of service where a writ was duly served by more than one method. In that situation, the earliest date on which service is duly effected applies. Key takeaway The expanded and clarified service options under the New Arrangement are long overdue and will be welcomed by practitioners. They are expected to reduce procedural uncertainty and delay in cross boundary disputes. For businesses operating across Hong Kong and the Chinese Mainland, the New Arrangement is likely to facilitate more reliable litigation planning, clearer assessment of dispute timelines, and reduced scope for tactical delay arising from service difficulties. Taken together with broader developments in cross boundary judicial cooperation, the New Arrangement reinforces Hong Kong’s position as a forum capable of handling disputes with Chinese Mainland elements.