The monetary unit of Nepali currency is Nepali Rupee its short form is NRS. Its value of rupee come in 1, 2, 5, 10, 20, 25, 50, 100, 500, and 1000 in paper notes, the 1 and 2 and 25 are rare. There are coins of 1, 2 and rare with 5-rupee quantities. There is foreign currency exchange counters at an international airport. You can make a change upon your arrival at the airport. You better make change at stalls and banks. But you also can pay USD for the visa on demand at the airport ($25 USD for 15 days, $100USD/90 days.
Usually the star hotels in Kathmandu, Chitwan and Pokhara usually also exchange currency, but rates may differ from those you can find in foreign currently exchange stalls in Kathmandu. Therefore, if you are travelling out of Kathmandu you better make change and also take small currency, because, there are small business houses out of Kathmandu valley, which usually cannot provide change of larger amount such as Rs. 500 and Rs. 1000 rupee notes. One Indian National Currency (INR) is equivalent to 1.6 NRS (10 INR is 16 NRS, and 100 INR equals 160 NRS).
There are several Automated Tailor Machines (ATMs) machines in Kathmandu and some of major cities across the country, but the cash retrievable is limited with maximum to 25,000 NRS (under $250 USD). Therefore, you better bring cash to avoid successive ATM charges. Many banks have their branches in most of Nepal’s district headquarters and major cities across the country such as Chitwan, Pokhara, Lumbini and so forth. But, these branch offices rarely provide the facility of foreign currency exchange facilities. The exchange rate of foreign currency often keeps fluctuating.