Just returned from a trip to Laos: Vientiane/Vang Vieng/Luang Prabang. Didn’t use ATMs at all due to charges. Found the best GBP LAK cash conversion rates at moneychangers in Vientiane on Ave Lane Xang, just a bit further up from Talat Sao Mall toward the Patuxay monument on the right side of the road. The conversion rates in Vang Vieng were not as good.