Bit late I know, but thought it worth a try anyway. It's my boyfriends birthday tomorrow and I would like to take him to a fancy hotel to use the swimming pool for a couple of hours if the weather is nice. I'm not sure if all big hotels will let outsiders pay to use the pool and I sort of want to plan where we're going before we go there. Any recommendations would be lovely, and any other ideas are welcome too of course, open to all random suggestions for birthday fun!
you might want to try the hanoi expat website.Lots of good info there. I did stay in the Sofitel plaza which has a great pool but don't know if outsiders can pay. anyway check this link out.
Sorry - probably far too late but anyway ... As far as I'm aware you can use the pool at the Daewoo Hotel for $10 each. It's a bit out of the centre of things but only about 50,000 in a taxi. I've not been in it but the pool looks wonderful and during the day is very quiet. You should call first to check though.
There's also one at the Army Hotel (nr the Vietnam History Museum) which is 70,000 VND but I wouldn't class that as a fancy hotel!