If I go to usa for 90 days stay how long do I have to be out of usa before I can return for another 90 days?

No...there is no such thing as that "90 day" rule. You must return to your home country between visits, but there is no specified time between visits. You may spend a total of 180 days in any given year in the U.S. under the vwp. The embassy website does not cover this info. One time I found somethng in writing on this on an obscure site, but I cannot find it now. I have also seen replys from other travelers who have come back under the vwp after just a short time back home. I really would like to give you something in writing to confirm this, but right now just cannot find anything...but I assure you this is correct. You could also consider applying for a B2 visa. It is easy, and you are not limited to the 90 days...and can apply for an extension if you want to stay longer. I think the U.S. gov't is vague on this as they leave the decision on whether or not to let you back in up to the immigration officer at customs. If you can prove you have ties back home, have money to support yourself, and have never violated visa conditions in the past, they let you come back.

You have to leave the US for 90 days in order to return for another 90 days.

I had to do this when I went to Germany-90 days in Germany, 90 in US, 90 in Germany, etc.

I had thought 90 days.

That's what i was planning to do.

USA-90 days

Canada -90 days

And then the USA for 90 days again.

Be aware that you may get questioned.

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