The Nepal Tourism Board’s customs page is short enough to read in full before you land at Tribhuvan, and it stays short on purpose: some obvious questions simply are not on it.
Declare, then pick your channel
“All baggage must be declared and cleared through the customs on arrival at the entry point.” From there, the airport splits arrivals into two channels.
Carrying nothing dutiable, take the fast route: “Passengers arriving at Tribhuvan International Airport (TIA) without any dutiable goods can proceed through the Green Channel for quick clearance without a baggage check.”
Carrying dutiable articles, the alternative is direct: “you have to pass through the Red Channel for detailed customs clearance.”
Personal effects travel free
“Personal effects are permitted free entry.” No further conditions are attached to that sentence on the Nepal Tourism Board’s page.
The duty-free list, as published
The published duty-free list: “visitors are allowed to bring to Nepal free of duty: cigarettes (200 sticks) or cigars (50 sticks), distilled liquor (one 1.15 liter bottle), and film (15 rolls).” Fifteen rolls of film is the number on the page. We are reporting it as published, not adjusting it for how anyone actually travels now.
A second list covers equipment you can bring in duty-free on condition you take it home with you: “binoculars, movie or video camera, still camera, laptop computer, and portable music system.” Bring them in, leave with them, and no duty applies. The page does not say what happens if you don’t, whether duty becomes payable retroactively or something else, and we are not going to guess.
Taking cultural items out is restricted, not just discouraged
Exporting antiques needs sign-off from a specific office: “The export of antiques requires special certification from the Department of Archeology, National Archive Building, Ram Shah Path, Kathmandu.”
Some categories cannot leave at all, certification or not: “It is illegal to export objects over 100 years old, such as sacred images, paintings, manuscripts that are valued for culture and religious reasons.”
No penalty, cash threshold, or value limit is published
This page stays thin on enforcement. There is no stated penalty for failing to declare dutiable goods, no published threshold for carrying foreign cash, and no general duty-free value limit the way some neighboring customs pages publish one. If your trip involves anything beyond the specific list above, this page will not give you a rate; ask Nepal Customs directly rather than assume a figure.
Which channel to pick, and when to check certification
Carrying only personal effects, the tobacco or liquor ration, and electronics you will take home with you, the Green Channel is yours. Carrying anything beyond that, or unsure, take the Red Channel and let a declared exception get sorted rather than discovered later. And if you are buying anything that looks old, ask about the certification before you buy it, not after.