When you enter the TAR from Nepal, you have to go by completely different rules from when entering from the rest of China. When you enter from Nepal, you have to be on a group Chinese visa. Only travel agencies in Kathmandu can arrange a group Chinese visa for you. You can’t get it on your own. There is no way around this. Before, you had to be with a group of four or five people, but now you can get a group visa with only two people and in rare cases even one person. DO NOT get a Chinese visa in your passport before you arrive in Nepal. If you do, it will be cancelled and you will have wasted your time and money. You cannot enter the TAR from Nepal on a regular Chinese tourist visa…it MUST be a group visa. The group visa is usually a piece of paper. It is not stamped in your passport like a normal visa. The group Chinese visa is usually valid for only 21 days, though sometimes they will give you 28 days. From Kathmandu, Nepal you have the option of flying or taking a 4WD to Lhasa. You have to arrange all travel through a travel agency. You cannot buy a ticket to Lhasa on your own. You also have to have a Tibet Travel Permit and Alien Travel Permit that a travel agency must arrange for you.
There are now flights year round between Kathmandu and Lhasa. The one-way flight is only an hour, but it is not cheap. Expect to pay over $300 for the flight, visa and permit. Many people take a 5 to 7 day overland trip to Lhasa going through Everest Base Camp, Shigatse, Gyantse and Yamdrok Lake. This overland trip also is not cheap. About the cheapest you will find it is for around $475 per person (you can do the trip in reverse starting in Lhasa for around $150 per person). There are many, many travel agencies in Kathmandu that can arrange travel to Lhasa. Shop around and feel free to negotiate on the price.
Try and avoid getting a Chinese group visa with a stranger. With a group visa you have to enter and exit China together. So if you get put on a group visa with someone you don’t know and he plans to exit China through Mongolia and you plan to exit through Vietnam, you are going to have some problems because your group visa is only on one piece of paper. If you are on a group visa with people you plan to exit China with, then you will be fine. A lot of people try and change their group visa into a standard Chinese visa once they leave the TAR (also known as splitting the visa). It is not possible to change or split your visa in Lhasa or anywhere in the TAR. Places like Golmud and Xining in Qinghai province are known to change people’s visa’s while places like Chengdu and Kunming sometimes will not. It is very difficult to extend a group Chinese visa beyond the 21 (or sometimes 28) days given to you. That is another reason people try and change the group visa into a regular tourist visa. Regular tourists visa’s can easily be extended an additional 30 days at most PSB offices in China. If you plan on entering Tibet with a group and exiting China with the same group within the validity of the group visa (21 to 28 days), you will be fine. It is much easier and cheaper to begin your trip in China and then go to the TAR rather than starting from Nepal. From China, you can travel to Lhasa on your own. From Nepal, you have to go with a group. For more information on entering the TAR from Nepal contact (tell them Losang recommended you):