answered about 7 months ago by Annett

Jeff, I had the same issue. I booked a tour to Halong bay and they required the passport for the overnight stay. In this case, the copy of my passport was ok for them. However, I doubt whether you could use just a copy when you take a flight.
Don't even bother to try it for flights, absolutly no way. If you have a residence card, that is accepted, well it was 4 years ago, not tried it since.
Photocopy will be a hit and miss affair for the hotels as well, but if you stay at the medieum to low end places, they will bend the rules for the money.