About Visa waiver program?

Question

Is there any limitations/restrictions on the visa waiver program, I'd like to know how many times a year can I enter The USA under this program? and how much time between every two vists?

Answer 1

There is no hard and fast rule, but CBP looks for evidence that the applicant for admission is not using the visa waiver to live in the US. Here are some FAQs:
http://www.cbp.gov/xp/cgov/travel/id_visa/vwp/vwp.xml

Note especially the question about being readmitted after a brief visit outside the US: you can see that they will readmit you for the balance of the original 90-day maximum, not for a whole new 90 days.

two visits per year of 90 days each might be just about the most they will allow without raising eyebrows. Or, of course, many visits of a few days or a couple of weeks each in the case of businesspeople or others who can explain their need for frequent small trips.

Answer 2

I don't really know how many times a year you're allowed to enter the U.S. under this program ... but I do know that my friend's Swedish girlfriend, before they were married, entered the U.S. 3 times in the same year, staying 3 months ... went home for one month ... came back again for 3 months ... went home for one month ... etc., etc. She had no difficulty doing it ...