How long is the transit visa issued at Beijing airport now?

They are not issued at all; transit visas upon arrival in China are not provided. Instead, for transit through Chinese airports and ports, citizens of Russia and other countries can obtain a visa-free transit. Visa-free transit is a fundamentally different type of permit, processed more simply and free of charge. Currently, visa-free stay in China gives the right to stay in the country for up to 240 hours, but with certain conditions. More details are described here - https://nashaplaneta.net/besopasnost/novye-pravila-tranzita-cherez-kitaj-10-dnej-bez-vizy

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