Haw. Rev. Stat. § 652-2.5: Service on garnishee.

Service of the copy upon the garnishee may be made in any of the manners here described, namely:

(1) If the garnishee lives or has an office in the district in which process is issued, by the sheriff, deputy sheriff, police officer, or independent civil process server from the department of law enforcement's list under section 353C-11 handing a copy to the garnishee in person or leaving it in the garnishee's office in charge of some deputy or clerk or other employees or attache of the office; or

(2) If the garnishee lives in a district other than that in which the process was issued, by the sheriff, deputy sheriff, police officer, or independent civil process server handing a copy to the garnishee in person, or by mailing it in a sealed envelope, registered or certified, postage prepaid, return receipt requested, and addressed to the garnishee's last known home or business address.