Originally Posted by
snod08
THe OP will be riding after 11PM...there will be a 50% midnight surcharge.
Just to clarify, the OP might NOT be riding after 11PM (actually midnight). Changi clearance procedures can be very fast - if a passenger is walking off the jetway at say 11:05 it's quite possible for him/her to be home or wherever they want to be by 12 midnight (they can be waiting on the taxi line anwhere between 15-25 minutes later). In any case the midnight surcharge kicks in at midnight itself. So any part of the ride that takes place before midnight will not get surcharged.
yihao69's calculation above sound about right.