There are a lot of low-quality sites if you Google this, and they don't have the same prices. So please don't answer by copying the first Google hit.
Two months ago I crossed from Thailand to Laos at Friendship Bridge #1 from Nong Khai to Vientiane.
For years the price of the visa on arrival had been $30 USD for Australian citizens. It has gone up $40 for almost all countries.
Now even though I had perfect condition USD from before covid in my wallet and even though I'd gone to SuperRich in Khon Kaen on my way north to buy new USD, the Laos immigration people rejected every one of my US banknotes. Apparently perfect condition is not good enough, they must now be 100% mint and uncirculated! (Let me know if the why of this would itself be an on-topic question here.)
As it happens there is at least one bank with moneychangers and at least one ATM right in the immigration area. I was able to change some Euros I forgot I had, though they rejected at least one of my Euro banknotes, they were less fussy than they were with the USD. (The exchange rates seemed fair.)
Now I'll be crossing from Nong Khai back into Vientiane again in another three days. I have some Lao Kip left and I have some Thai baht left, but I'm not sure I have enough of either - maybe. I know I can change one of my currencies in town here before I get to the border.
I was a bit grumpy last time after they rejected my USD so I didn't remember if they had a chart of the prices in each currency or if they only told me the ones I asked about. I do know that they accept Thai Baht but that the price is higher than for USD, but they don't have ridiculous standards for the condition of the Thai banknotes, so it's probably worth it.
So can anyone tell me the true rates in each accepted currency?
Do they accept USD, THB, and LAK? Any others?
If somebody has a link to the official Lao government fees that would be perfect. So would a photo of any chart that might be on display at the border. So will you recent experience.
If not, I will do my best to gather this info and post an answer in three days. But Ideally I'll find out exactly how much money I need to set aside or exchange before then (-: