Udayapur is synonymous with the biggest cement factory in Nepal- Udayapur Cement Factory was founded in 1987. Since 2011, Siddhipuri Village has produced turmeric worth millions of rupees annually. Udayapur is also known for its holy cow smuggling route. Slaughtering cows is illegal in Nepal, and the area is known for smugglers who buy cows from Khotang and Okhaldhunga, which are then taken to Beltar Bazar, Udayapur. From there, they are easily smuggled to India.