By plane
The grandly named Ubon Ratchathani International Airport IATA: UBP, ICAO: VTUU in reality serves only flights to Bangkok most of the year. Thai Airways has two daily non-stop flights between Bangkok and Ubon and return. NokAir has three daily non-stop flights between Bangkok Don Muaeng Airport and Ubon and return. Air Asia has two daily non-stop flights between Bangkok and Ubon and return year-round. AirAsia operates 3 weekly flights between Phuket and Ubon from October to March and between Chiang Mai and Ubon from November to March. Flight time is 50 minutes in Airbus A320 or Boeing 737 aircraft.
The airport is at the northern edge of the city almost within walking distance, but accommodation is scattered around Ubon, so better not to consider walking. Much better to go to one of the two limousine taxi counters that are located in the airport arrivals hall and purchase for only 100 baht a taxi coupon that will take you to almost any point in the city. Limousine taxi rates in Ubon are extremely cheap by Western standards and lower than those in Bangkok. Set prices have been established to most destinations in and around Ubon. A taxi from Ubon to Chong Mek costs only 1,000 baht for the 90km one way trip and a taxi from Ubon to Mukdahan costs 2,000 - 2,500 baht depending on the vehicle type to travel a one way distance of 192km. The driver does not charge for the return trip like some western countries. There are no taxi meters and the fare must normally be purchased from one of the two taxi counters at the airport arrivals desk.
If you prefer not to take a fixed price taxi, you can always walk the 200 metres beyond the general airport parking area to haggle with the waiting tuk-tuk drivers, but chances are that your trip will end up costing you more.
By train
Daily trains connect with Bangkok and stop at all the southern Isaan provincial capitals Si Saket, Surin, Buriram, and Nakhon Ratchasima (Khorat). The station is to the south of the city on the opposite side of the Mun River in Warin Chamrap; buses 2 and 6 connect to the center.
One option is to catch the overnight night express train from Ubon Warin Chamrap station to Bangkok. Train departs at 18:30 and arrives Bangkok at 05:30. Travel first class in a two berth private sleeper compartment with fresh starched sheets and pillows for a little over 2,000 baht per couple. Travel is also available in 2nd class sleeper seats and 3rd class seats for a lower cost.
By bus
Buses to Bangkok take 10 hours due to stops and arrive near the BTS station known as Mo Chit or Mo Chit Mai, in the north part of the city. The Nakhon Chai Air private bus company (http://www.nca.co.th/web/...) also has frequent, well-maintained buses that ply the route and also leave from the Ubon bus terminal, but arrive at their own private terminal in Bangkok, near the main Mo Chit terminal.
Ubon is less than 100 km from the Lao border at Chong Mek / Pakse. A regular bus service now operates direct from Ubon bus station near the "Big C" shopping complex to Pakse in Laos, and caters for travellers who wish to obtain a Lao visa on arrival it waits for all passengers to complete immigration and visa formalities before continuing to Pakse. The fare is 200 baht.