量差计入签证吗？
首先解释下Visa On Arrival (VoA)，它是一个落地签的意思。 其次要介绍下visa waiver program， 这个是免签证入境。 美国的VOA和加拿大的VOA都不属于这两个概念的范畴哦！ VISA Waiver Program is an agreement between the U.S government and participating countries， allowing citizens of those counties to travel to the USA for up to 90 days without a visa as long as they meet certain criteria：
1、 Must have a valid passport issued by one of the eligible countries；
2、 Should not be inadmissible on any other ground;and
3、 Have a machine readable passport， with an entry/exit stamp within the past 15 years or an electronic record indicating previous entries into United States（this can even include cruise ships）.
As you can see， having a VoA doesnt mean that anyone from anywhere can just come over here with no paperwork whatsoever．If your country isn’t part of this program， then it doesn't exist. This also means that once you get back home， there would probably be some issues to face if you want to re-enter because most VOA’s are only good for single trips rather than multiple entries which may require visas depending upon when you first entered the US（if at all）.
On top of everything above mentioned， we should clarify what kind of document should accompany our Passport： A machine readable Passport with an eTA application form attached. So basically it has to contain the details about your application but its still considered as "paperwork" required along side another legal instrument namely Machine Readable Passports. If someone tries coming through using such documents， he will fail both tests： eTA test & machine readability check. This might cause him much trouble later down since his Passport won't pass muster either way！ Hence why we say don’t mess around please ;） There aren't many countries offering Visa on arrival services anymore nowadays so it shouldn't really ever happen unless there was some sort mistake made somewhere along line while processing their applications via different channels outside Government websites like ours who do take full responsibility of what goes