Nepal Telecom (NTC) and Ncell dominate mobile service, and your choice between them matters more here than in most countries because the gap in coverage widens dramatically once you leave the Kathmandu Valley. NTC holds the infrastructure advantage in remote regions — Manang, Upper Mustang, the Khumbu past Namche Bazaar — where Ncell signal becomes intermittent or disappears entirely. Ncell often delivers faster data speeds in urban areas and along major trekking corridors below 3,500 meters, but NTC is the reliable choice if your route includes anything genuinely remote. Both carriers operate SIM registration desks in the arrivals hall at Tribhuvan International Airport immediately after you clear immigration, and this is where most travelers purchase their cards because the alternative — visiting a carrier store in Thamel — adds an unnecessary errand to your first day. Registration requires your passport and a passport photo, though the airport desks sometimes waive the photo requirement. A tourist SIM with data runs between 500 and 1,000 rupees depending on the data package you select, and activation happens within minutes.
4G coverage exists throughout Kathmandu, Pokhara, and along the main highway corridors, but altitude degrades connectivity in predictable ways. Between Lukla and Namche Bazaar you will still find workable 4G on NTC. Past Namche the signal weakens. By the time you reach Dingboche at 4,410 meters, 4G becomes unreliable even when technically present, and above that elevation you should plan for the absence of connectivity rather than its occasional appearance. The teahouses along popular routes like the Annapurna Circuit and Everest Base Camp Trek often offer paid WiFi, but the service runs on the same degraded cellular infrastructure and performs accordingly — adequate for messaging, unusable for video calls, and prone to multi-hour outages when weather disrupts the solar panels that power the relay towers.
Satellite communication devices make sense if you are trekking in genuinely remote regions where even NTC coverage fails or if you need reliable emergency contact capability regardless of infrastructure. The Garmin inReach models are the most common among trekkers, and rental shops in Thamel stock them alongside oxygen meters and down sleeping bags. Kathmandu and Pokhara both support remote work if your requirements are modest — coffee shops in Thamel, Jhamsikhel, and Lakeside Pokhara run stable fiber connections, and coworking spaces like Workstation Nepal in Lazimpat offer dedicated desk setups with reliable power backup, which matters more than bandwidth during the frequent load-shedding hours that still occur outside peak tourist seasons.