Hong Kong is 16 hours ahead of Portland during standard time (or 15 hours during PDT). Portland uses Pacific Time (PT, UTC-8/-7) while Hong Kong uses Hong Kong Time (HKT, UTC+8). When it's 12:00 PM in Portland, it's 4:00 AM the next day in Hong Kong.
Hong Kong does not observe daylight saving time, so the difference varies between 15 and 16 hours depending on whether Portland is on PST or PDT.
Best calling time: 5:00 PM - 7:00 PM Portland time. This corresponds to 9:00 AM - 11:00 AM the next day in Hong Kong, catching morning business hours.
The substantial time difference means crossing the International Date Line conceptually. Portland's tech and outdoor goods companies have trade relationships with Hong Kong. Evening calls from Portland reach Hong Kong's business morning.