If I arrive at the airport of Udon Thani around 7 am, is it possible to apply for a Visa at Vientiane the same day ?

And is there a direct bus from the airport to Nongkhai ?

There is a Mini bus that runs from the airport to the border. You should make it in time.

Collect your passport the next day afternoon.

Thanks.

If you are in Bangkok, if at all possible, you should get your PDR Lao Visa there and not try to get it at the Friendship Bridge -- sometimes at the Bridge it will take 10 minutes and sometimes it can take more time than your flight time from Bangkok to UTH.

I hear from people here that "same day" is almost impossible. It takes one day.

There is a "big" bus running from the Udon busstation centre of town to the bridge and Vientiane. Takes about 1 h. Since same day is not possible buy your Lao visa at the bridge. You need one photo and US$ or baht. Go to the embassy, queue up and do your things. Take a hotel and pick up your passport next day.

Next day the evening flight back to BKK. Book in advance. It might be busy. Or take the evening trains from Nongkhai. "Sleeper", comfortable and much cheaper. But also the train must be booked in advance.

I hear from people here that "same day" is almost impossible. It takes one day.

There is a "big" bus running from the Udon busstation centre of town to the bridge and Vientiane. Takes about 1 h. Since same day is not possible buy your Lao visa at the bridge. You need one photo and US$ or baht. Go to the embassy, queue up and do your things. Take a hotel and pick up your passport next day.

Next day the evening flight back to BKK. Book in advance. It might be busy. Or take the evening trains from Nongkhai. "Sleeper", comfortable and much cheaper. But also the train must be booked in advance.

Please don't complicate an easy process with talk of buses from bus stations.

Just take the 200 baht minivan (called a limousine) directly from the airport to Friendship Bridge...in 45 minutes. With waiting time you'll be at the Bridge at 8am.

I've done this trip (arriving 7am at the airport on Nok Air) twice in the last 3 months (once during the SEA games) and both times I was at the Thai Consulate by 9:30am. Even if the Laos VOA took a bit longer, you'll still make it on time.