涵涵君的小站中文
在中国转机，最容易出错的两件事是“要不要过境签”和“行李能不能直挂”。同样是在上海转机，联程票和分开买的票，走的是两条完全不同的通道。
- 过境免签的适用条件：24小时过境免签对所有国家开放、适用全部对外开放口岸，条件是持前往第三国（地区）的联程客票、有确认座位的机（船、车）票，且不离开口岸限定区域；240小时（10天）过境免签适用57个国家，须持普通护照和前往第三国（地区）的联程客票，从指定的65个对外开放口岸入境，在规定区域内停留。
- 不同机场的转机流程：持同一张客票、行李已直挂的国际转国际航班，通常走国际中转通道，不办入境手续；国际转国内航班必须办理入境边检和海关手续，再重新安检；需要换航站楼的，还要额外留出换楼和二次安检的时间。
- 行李是否直挂：取决于是否同一张客票、承运航司之间有没有联运协议。同一张票、同一航空联盟或已签联运协议的航司，一般可在始发站直挂到最终目的地；分开购买的票通常要提取行李重新托运，也就意味着必须先入境。
- 留多少时间够：最短衔接时间由机场和航司设定，出票时会给出。一般来说，同一客票的国际转国际留2小时以上、国际转国内留3小时以上更稳妥；分开购票要留得更宽裕，因为前段延误、后段航司不承担衔接责任。
- 能不能出机场：24小时过境且不离开口岸限定区域的，不需要签证，也不能出机场；确实需要离开限定区域的，须先向口岸边检机关申请临时入境许可。想正常进城，需要有效中国签证、居留许可，或者符合240小时过境免签条件并从指定口岸入境。
- 误机怎么办：同一张客票由承运航司负责改签后续航班；分开购票的后续行程需自行处理。在机场滞留时要注意签证或免签停留期限，不要因为等航班而逾期停留。
买票时最关键的判断是“一张票还是两张票”。订票平台上标注“组合航班”“自行中转”的，多数是两张独立客票：价格便宜，但行李要重新托运、误机风险自己承担。
出发前核对三件事：是不是同一张客票、行李能不能直挂到最终目的地、转机是否需要换航站楼。这三条决定了你在中转机场走哪条通道、需要留多少时间。
政策细节以国家移民管理局公告和承运航司通知为准。240小时过境免签的国家名单和口岸名单会调整，出行前请再核对一次。
以上为一般性说明，具体要求与最新规定以官方发布为准。
English
Layovers in China: Do You Need a Transit Visa and Can You Leave the Airport
Two things go wrong most often on a China layover: whether you need a transit visa, and whether your bags are checked through. Transferring in Shanghai on a single ticket and transferring on two separately booked tickets are two completely different processes.
- Transit without visa conditions: the 24-hour rule is open to all nationalities at every open port, provided you hold a connecting ticket to a third country or region with confirmed seats on a flight, ship or train, and you stay inside the port's restricted area. The 240-hour (10-day) rule applies to 57 countries and requires an ordinary passport plus an onward ticket to a third country or region, entry through one of 65 designated open ports, and stay within the permitted areas.
- Transfer procedures vary by airport: on a single ticket with bags checked through, an international-to-international connection usually uses the international transit channel without clearing immigration. An international-to-domestic connection requires immigration and customs clearance, followed by a fresh security check. If you must change terminals, allow extra time for the transfer and a second screening.
- Checked-through baggage: this depends on whether you hold one ticket and whether the airlines have an interline agreement. With a single ticket, the same alliance or an interline partner, bags can usually be tagged to the final destination at your origin airport. Separate tickets normally mean collecting your bags and checking in again, which also means you must clear immigration.
- How much time to allow: minimum connecting times are set by airports and airlines and appear when you book. As a rule of thumb, allow at least two hours for an international-to-international connection on one ticket and three hours or more for international-to-domestic; leave more room on separate tickets, because the onward airline has no obligation if the first flight is late.
- Leaving the airport: if you are in 24-hour transit and stay inside the restricted area, you need no visa and you cannot leave the airport. If you genuinely need to leave the restricted area, apply first for a temporary entry permit from the border inspection authority at the port. To go into the city normally, you need a valid Chinese visa or residence permit, or you must qualify for 240-hour visa-free transit and enter through a designated port.
- Missed connections: on a single ticket, the operating airline is responsible for rebooking your onward flight. On separate tickets you handle the onward leg yourself. While stranded at the airport, keep an eye on your visa or visa-free stay limit so you do not overstay while waiting.
The key decision when booking is one ticket or two. Itineraries labelled as combined flights or self-transfer are usually two separate tickets: cheaper, but you must reclaim and re-check your bags and you carry the risk if a connection is missed.
Before departure, confirm three things: whether it is a single ticket, whether your bags can be tagged through to the final destination, and whether the transfer involves a change of terminal. These three answers determine which channel you use at the transit airport and how much time you need.
For policy details, follow the announcements of the National Immigration Administration and the notices of your operating airline. The country and port lists for 240-hour visa-free transit are revised periodically, so check them again shortly before you travel.
The above is general guidance only. For specific requirements and the latest rules, please refer to official announcements.
