Haw. Rev. Stat. § 578-7
Upon the filing of the affidavit referred to in section 578-6, the court may order service of the notice prescribed in sections 578-2 and 578-4 to be made as follows:
(1) Personal service or service by registered mail without the State. If the residence of a nonresident legal parent is known or is ascertained at any stage of the proceeding prior to the filing of a return of service pursuant to section 578-5, the court may order that service of notice of the time and place of hearing of the petition and of a copy thereof and of a copy of the court's order be made upon the parent by:
(B) Sending certified copies of the petition and of the notice of the time and place of the hearing thereof and of the court's order, by registered mail, addressed to the parent, with request for return receipt, which service, evidenced by the receipt signed by the parent and returned to the clerk of the court, shall be regarded as equivalent to service by publication or in lieu thereof.
When service is made pursuant to this paragraph, the time appointed for the hearing of the petition shall be not less than twenty-one days subsequent to the date of service as provided in this paragraph.
[L 1919, c 3, pt of §1; RL 1925, §3038; am L 1931, c 74, §1; RL 1935, §4524; RL 1945, §12275; am L 1953, c 115, pt of §1; RL 1955, §331-7; HRS §578-7; am L 1973, c 211, §3(e); gen ch 1985; am L 2018, c 18, §47]
Service by certified mail, see §1-28.