There are no direct long-haul flights to Tibet. You will probably have to stop over in Kathmandu, Chéngdū, Guǎngzhōu or Běijīng, even if you are making a beeline for Lhasa, especially considering you need to to pick up your permit in your chosen gateway city before heading to Lhasa.
For China, you generally have the choice of flying first to Běijīng (http://en.bcia.com.cn), Shànghǎi (http://www.shairport.com), Guǎngzhōu (www.guangzhouairportonline.com) or Hong Kong (http://www.hongkongairport.com); there is also a small but growing number of international flights direct to Chéngdū (http://www.cdairport.com/index.jsp). There’s little difference in fares to these airports, though fares can fluctuate by the day (Monday and Tuesday flights are generally cheaper than Friday and Saturday flights). There are direct flights from Běijīng and Shànghǎi to Lhasa, so it is no longer necessary to first fly into Chéngdū.
Generally speaking, long-haul flights to/from Kathmandu are relatively expensive, as a limited number of carriers operate out of the Nepali capital. The national carrier, Nepal Airlines, is notoriously unreliable and is to be avoided if possible. One option is to buy separate discounted flights to Delhi and from Delhi on to Kathmandu, but note that without a single through ticket you will likely have to arrange an Indian transit or tourist visa in order to pick up your baggage and transfer between flights at Delhi airport.
International airlines flying into and out of Kathmandu include the following.
Air Asia (www.airasia.com) Low-cost carrier from Malaysia. Direct flights from Kuala Lumpur.
Jet Airways (www.jetairways.com) Good connections to Delhi.
Nepal Airlines (www.nepalairlines.com.np) The flagship carrier of Nepal.
Thai Airways (www.thaiairways.com) Popular flights from Bangkok.
Turkish Airlines (www.turkishairlines.com) Good connections from Europe via Istanbul.
Chéngdū's Shuangliu International Airport is well connected to other cities in China, with daily flights arriving from Běijīng, Shànghǎi, Guǎngzhōu, Kūnmíng and Hong Kong among others. There is also a growing number of international carriers making nonstop flights into Chéngdū, mainly from Asian hubs like Bangkok, Kuala Lumpur, Seoul, Tokyo and Singapore. From Europe it’s possible to reach Chéngdū nonstop from Amsterdam, Frankfurt and the UK, and from the USA there are direct flights from Los Angeles and San Francisco. Arriving from other international destinations will likely require you to change planes and possibly make a layover in a mainland Chinese hub.
International airlines flying into Chéngdū include the following.
Air Asia (www.airasia.com) From Kuala Lumpur.
Air China (www.airchina.com) From Frankfurt, Hong Kong, Kathmandu, Paris, Rome, Singapore, Sydney and Tokyo.
Asiana (www.asiana.com) Via Seoul.
British Airways (www.britishairways.com) From London.
China Eastern (www.flychinaeastern.com) From Bangkok and Los Angeles.
Etihad (www.etihad.com) Via Abu Dhabi.
KLM (www.klm.com) From Amsterdam.
Qatar Airways (www.qatarairways.com) Via Doha.
Sichuan Airlines (www.scal.com.cn) From Bangkok, Melbourne, Seoul, Singapore, Tokyo and Vancouver.
United Airlines (www.united.com) From San Francisco.
Departure tax in China is worked into the price of both domestic and international tickets, so there’s nothing additional to pay at the airport.
There are essentially two ways to buy an air ticket to Tibet's gateway cities; buy a single international ticket to a city like Chéngdū or buy an international ticket to Běijīng, Shànghǎi or Guǎngzhōu and then buy a discounted domestic Chinese air ticket online.
Note that if transiting through a city like Běijīng en route to a domestic Chinese destination you will need to clear immigration and customs in Běijīng, so allow plenty of time for your domestic connection.
You can buy discounted domestic tickets within China from online Chinese ticket agencies such as Elong (www.elong.net) and Ctrip (http://english.ctrip.com). These latter sites will not sell you a ticket from Chéngdū to Tibet without Chinese ID, but international online ticket sites such as One Travel (www.onetravel.com) and Expedia (www.expedia.com) will. If this all sounds too complicated, you can always ask your Tibetan tour agency to handle domestic tickets to Lhasa.
Airfares to China peak between June and September.
Within China there are flight connections to Lhasa from a dozen cities (and growing), including direct flights from Běijīng, Guǎngzhōu, Lánzhōu, Xi'an, Xīníng and Kūnmíng.
There are also some interesting, but less frequent, flights within the Tibetan world, namely from Lhasa to Yùshù (Jyekundo) in Qīnghǎi, Xiàhé in Gānsù, Kàngdīng in Sìchuān and Déqīn (also known as Zhōngdiàn, Gyeltang or Shangrila) in Yúnnán.
That said, most travellers still fly in from Chéngdū, as there are more flights, cheaper fares and more tour agencies there.
Your Tibet permit will be checked when checking in for your flight to Lhasa, as well as on arrival at Lhasa’s Gongkar airport.
Note that flights to and from Lhasa are sometimes cancelled or delayed in the winter months, so if you are flying at this time give yourself a couple of days’ leeway if you have a connecting flight.
Baggage allowance on flights to Lhasa is 20kg in economy class and 40kg in 1st class, so you’ll have to limit your gear to avoid penalties, regardless of what you are allowed to bring on your international flight into China.
Air China and Sichuan Airlines operate flights between Kathmandu and Lhasa three to four times a week in the high summer season. From April to October flights drop to around once or twice a week.
Individual travellers can’t buy air tickets from the Air China office in Kathmandu without a TTB permit. To get a ticket you’ll have to purchase a multi-day package tour through a travel agency. This includes flight ticket, airport transfers, TTB permit and accommodation.
It is possible to buy air tickets from Kathmandu to other destinations in China; you don’t need a TTB permit to take these flights.
Chéngdū has long been the main gateway to Lhasa for travellers coming by air, and multiple flights a day go to Lhasa in the height of summer. Flights cost ¥1680 one way but can be discounted to as low as ¥1000.
Flights into Lhasa are operated by Air China (CA; www.airchina.com.cn), Sichuan Airlines (3U; www.scal.com.cn), Tibet Airlines (TV; wwwtibetairlines.com) and China Eastern (MU; www.ce-air.com). Note that on many online booking sites you need to spell Lhasa as 'Lasa'.
Try to book the first flight of the day because weather conditions and visibility will be optimal in the morning. On a clear day the views from the plane are stupendous, so try to get a window seat. In general the best views are from the left side of the plane from Chéngdū to Lhasa and the right side from Lhasa to Chéngdū. Getting into Lhasa early also gives you a little more time to acclimatise if you are on a short tour.
If you are coming to Tibet from somewhere outside China, have your agency mail your permit to a hotel in Chéngdū, where you can pick it up and fly out the next day. Make sure the permit is sent a few days before you arrive and that you confirm its arrival.
There are also daily flights (¥1530) from Chéngdū to Nyingtri (Línzhī) in eastern Tibet, which might be an option if you plan to visit the Kongpo region. At around 3000m elevation, the region is lower than Lhasa and so helps with acclimatisation.
There are some useful flight connections between Lhasa and the popular traveller centres of Lìjiāng, Kūnmíng and Déqīn (the main airport for Zhōngdiàn, also known as Gyeltang or Shangrila). As with other flights to Lhasa, foreigners won’t be allowed on board without a TTB permit.