Underpaid mail items will not be accepted by the Immigration Department (ImmD). Hongkong Post will levy a surcharge on senders of local mail items addressed to offices of the ImmD without sufficient postage. Such underpaid items are subject to delay in processing and delivery. Should a sender fail to settle the surcharge by the stipulated deadline, he / she will be required to collect the mail item from the Central Mail Centre; otherwise, Hongkong Post will dispose of it as an undeliverable item in accordance with their established procedures. Local mail items without return address will be disposed of by Hongkong Post. In case of an underpaid mail item from a region outside Hong Kong, Hongkong Post will return it to its postal administration of origin in accordance with their established procedures.
For proper delivery of your mail items, please ensure your mail items bear sufficient postage with return address before posting.
Please visit the following link for detailed information: