So, the reciprocal question would be, when the receiver of my texts I send in Hong Kong (USA and local numbers within that country), when the person replies to me:
Person in USA is charged by their carrier as if they're responding to me in the USA. Nothing different than any other day.
Person in Hong Kong: is charged by their carrier as if they're responding to me as if I'm on a local Hong Kong number? No different than if I had a HK phone number?
Is my understanding of this correct? I'd hate to be running up the other person's phone bill with crazy charges because of not understanding how this works.
None of the responses or threads seems to be completely clear on this.
If the US person sends you (a US number) a text message, neither of you are charged.
If a HK person with a HK number sends you a text message, they may be charged based on what their carrier charges for international texting, but you are not charged as SMS is unlimited.