In accordance with the agreement signed between the United States and China to extend visa validity, beginning on November 29, 2016, Chinese citizens with 10-year B1, B2 or B1/B2 visas in Peoples’ Republic of China passports will be required to update their biographical and other information from their visa application via a website every two years, or upon getting a new passport or B1, B2, or B1/B2 visa, whichever occurs first. This mechanism is called EVUS - Electronic Visa Update System.
Some types of visa like B1 may not expire with the expiry of the holder's passport. An unexpired, endorsed visa in an expired passport may be presented for entry into the USA, as long as the visa itself has not been cancelled, is undamaged, is less than 10 years old and is presented with a valid non-expired passport, provided that both passports are for the same nationality.
Some countries apply the principle of reciprocity in their visa policy. A country's visa policy is called 'reciprocal' if it imposes visa requirement against citizens of all the countries that impose visa requirements against its own citizens. The opposite is rarely true: a country rarely lifts visa requirements against citizens of all the countries that also lift visa requirements against its own citizens, unless a prior bilateral agreement has been made.
When looking at a visa, you should be able to tell what type it is, how long it is good for, and whether or not multiple entries are permitted. Specific restrictions may also be written in, or indicated by the class of visa. For example, people with tourist visas are generally not permitted to work. If you aren't sure about the restrictions, be sure to ask immigration officials.
The Democratic People's Republic of Korea (North Korea) requires that its citizens obtain an exit visa stating the traveller's destination country and time to be spent abroad before leaving the country. Additionally, North Korean authorities also require North Korean citizens obtain a re-entry visa from a North Korean embassy or North Korean mission abroad before being allowed back into North Korea.
So, for example, someone who arrives in the U.S. with a fiancé visa (K-1) and applies for a work permit will receive one that lasts only until the 90-day termination of that person’s K-1 visa. Although it might sound like this would create problems for fiancés who plan to apply for green cards after marriage and stay in the United States, it actually doesn’t. That’s because the fiance can simply apply to adjust status as soon as they’ve gotten married, and then apply for an EAD that lasts even longer, at that time.
At present, 38 countries in the Visa Waiver Program are Andorra, Australia, Austria, Belgium, Brunei, Chile, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Monaco, the Netherlands, New Zealand, Norway, Portugal, San Marino, Singapore, Slovenia, Slovakia, South Korea, Spain, Sweden, Switzerland, Taiwan and the United Kingdom.
A country’s visa policy is a rule that states who may or may not enter the country. The policy may allow passport holders of one country to enter visa-free but not the passport holders of another country. Most visa policies are bilateral, meaning that two countries will allow visa-free travel to each other’s citizens, but this is not always the case. For example, Canadian passport holders may travel to Grenada visa-free, but Grenadians must apply for a visa in order to travel to Canada.