Does a third country need to sign a contract when transiting abroad?

This question is too general to answer. Transit city? Is it a connecting ticket? etc. For example, there are multiple airports in London, England. If you choose to transfer and not stay at the same airport, you will need a transit visa. For example, if you transfer to the same airport in Paris, you can usually use the transfer channel without a visa, but if your ticket is not a connecting flight, then you have to go to customs. Visas are required to handle checked baggage and onward flights. Therefore, specific problems must be analyzed in detail.

Transit does not require customs clearance, so no visa is required, except for the United States. Please click "Accept as best answer", thanks

It depends on which country you are transiting in, whether your luggage is checked through, whether you have checked your luggage through customs, and the airline you are flying with. <br/>For example, if you Beijing＝London＝Paris, transiting in London, you need a British visa no matter what the reason is;<br/>For example, if you Beijing＝Paris＝London, transiting in Paris, if it is Air France and the baggage is checked through, or If you have two different airlines but you have no checked luggage, you do not need a French visa;<br/>For example, if you connect in Cairo＝Rome＝Beijing, you transfer in Rome, and your luggage is checked through, or if you have two different airlines but you have no checked luggage, then Italy visa is not required;<br/>But if you Cairo＝Rome＝Athens＝Beijing, and you transit twice in the Schengen area, you need a Schengen visa<br/>So please tell me the specific situation, and I will tell you whether Visa required

Hello, <br/>In addition to the visa of the final destination country, whether the transit country needs a visa is not uniform, but most countries do not require that transit visa [as long as you don’t leave the airport], only a few National regulations: Even if you don’t go to the airport to transfer, you still need a transit visa, such as: the United States, Canada, Australia, and Myanmar, Malaysia, Mexico, etc.

You don't need a visa if you transit at the airport and leave the airport