Hello. You can use the B-2 but avoid any mention of the wedding. Don't lie, but don't bring it up either. After you marry and leave the U.S., you may have problems visiting the U.S. in the future on the B-2 because if they are aware of your marriage, they will assume you will just want to enter the U.S. to get Residency because you do not want to be outside of the U.S. to wait the 6 to 9 months of time it takes to get a K-3 spouse visa. In the future if you want to get Residency, then yes, you would need to do a K-3 spouse visa or a CR-1 visa:

1) The K-3 spouse visa takes 6 to 9 months, you must be married. The I-129F will cost $340 plus $420 for the I-130, and $350 for the visa processing fee. Then after you enter the U.S., you must still file the I-485 for $1070 and wait for the marriage interview about 5 to 7 months later.

2) The CR-1 visa (or IR-1 if your marriage is more than 2 years old) takes about 1 year or so. You must be married. The fees are $420 for the I-130, $330 for the visa processing fee, $88 for an Affidavit of Support fee. But once you enter the U.S., you enter as a Resident and you do not have to file (or pay for) an I-485 nor do you have to attend an additional interview. You just get your green card in the mail a few weeks later.

So the K-3 is faster but generally more expensive. The CR-1 (and IR-1) are slower, but generally cheaper. And no, there is no middle-visa that you can use to enter the U.S. while that process is pending. You will most likely have to wait outside.

Here is a link to all three:

http://travel.state.gov/visa/immigrants/types/types_1315.html

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