Most official airport websites list the minimum transit times between arriving and departing flights. I have checked the Airports of Thailand and the Suvarnabhumi sites. Not surprsingly, there is absolutely no information there (!) so it's difficult to assess if 90 minutes will be sufficient for you to change flights. However, TG recommends a minimum of 75 minutes if switching between their flights to a Star Alliance airline. This presumably means non-Star Alliance transfers should be longer.
I suggest you check quickly with the airline you are taking in to Bangkok to find out if 90 minutes is acceptable to it. A quick hop to Vientianne is surely preferable to an overnight bus trip.
|