Bhutan has some distinctive rules around tobacco and imports, rooted in its conservation and public-health values. Knowing them in advance avoids surprises at the border.
Tobacco
Bhutan was the first country in the world to ban the sale of tobacco. You may bring a limited quantity for personal use, but you must declare it on arrival and pay import duty, and you should keep the receipt with you. Smoking is prohibited in public places and around religious and public institutions, and designated smoking areas are very limited.
Customs declarations
On arrival you should declare items such as large sums of currency, professional camera, filming or drone equipment, and any plants, seeds or soil. The export of antiques and of religious or cultural artefacts is strictly prohibited without an official permit — so when buying handicrafts, ask the shop for proper documentation. Firearms, ammunition and narcotics are, of course, banned outright. Your guide can advise on anything you are unsure about.