Unitel, Lao Telecom and ETL cover towns and Mekong valleys on 3G and 4G; remote Bolaven Plateau tracks and northern Phongsali routes fade for long stretches. Luang Prabang old town stays connected. Check the network list above for Laos before you fly; it shows what is available right now, including options such as ETL Mobile.
There is no complicated Laos-only product to learn. NXTL is one global eSIM: the same profile you might use elsewhere works here on ETL Mobile when listed. Land, turn data on, and go — rates for Laos are shown live on this page because they can change.
Prepaid SIMs are sold at airports and Luang Prabang shops with passport registration. Data is cheap but speeds vary outside cities. That still makes sense if you will live in Vientiane for months and need local calls. For a holiday or short work trip, most people only need data — and NXTL gives you that without the desk stop: install at home, keep your usual number for calls and bank texts, pay only for the gigabytes you use.
If Laos is one stop on a longer route, NXTL is built for that. Use data around Vientiane and Luang Prabang, then keep the same balance wherever NXTL has coverage next. You are not locked into a single-country tourist pack.
Mekong slow boats between Huay Xai and Luang Prabang are offline for two-day journeys except near riverside villages. NXTL is built for that kind of Laos trip: data when you need it, without buying a new pack for every change of plan.
Before you fly to Laos, confirm your phone supports eSIM and is unlocked. Then install NXTL on Wi-Fi at home so you are not depending on airport Wi-Fi to get online in Vientiane.