Is there some kind of rules to follow when looking for the following? In particular I/we want to fly  Suvarnabhumi to Ubon Rat. ( Yes I know DMK is much cheaper btw)

For example which website offers best prices? Thai Smile direct or agents like Expedia etc.?

How how in advance ( For a specific date) is it best to book...Is there a sweetspot that generally offers best prices?

I also note for 3 people its cheaper to book separately . I'm not bothered about sitting apart for 1 hour...thanks

 

If you book and pay in Thai Baht (living in Thailand?) there is nothing to win with agents/search sites.

I always book directly on the ThaiSmile website.

It pays to book at least a month in advance.

 

After Songkran and into May all flights for 1250 Baht (BKK - UBP one way).

That's the final price incl. 20 kg baggage and seat selection.

With the cheapest price not all seats are available for reservation.

 

For the rest of March prices are significantly higher.

Around Songkran prices are nidicolous or fully booked.

 

If you are over 60 you are eligible for some "Senior" discount.