You can use a Credit Card, Master Card, or Visa Card in the major cities, especially in restaurants, cafes, and supermarkets. Likewise, payment in the hotels, travel agencies, and airlines are usually done in foreign currency. There can be a small charge while using these cards, therefore ask your bank. Make sure to keep the encashment receipt while making foreign exchange payments or transferring foreign currency into Nepali rupees. This will later help you to change left Nepali currency into different currencies before leaving the country.
You can find ATMs almost everywhere in the cities and towns. Almost all ATMs accept cards issued by international banking networks, however withdrawal limits can vary from Nrp 10,000 to Nrp 35,000 per day. As the majority of the payments are done in cash in Nepal, carrying a few cash is recommended. These days traveler's cheque is not accepted in Nepal. You can either visit banks or money exchange centers to exchange your money into Nepali currency. Do check the exchange rate before trading the money.