No.  Gambling at online casinos is not illegal in the United States.  And no, it is not legal either.  How can that be true?  Well, there are no active laws yet governing online casinos.  The closest thing was the Unlawful Internet Gambling Enforcement Act passed during the Bush administration back in 2006.  But even that did not make online casinos illegal, at most it made it illegal for banks to process transaction from online casinos.  But even that law has been put off.

Late last year Representative Barney Frank, Chairman of the House Financial Services committee managed to get a letter to the United States Treasury that requested that the implementation of the Unlawful Internet Gambling Enforcement Act be delayed until the middle of this year.  That means the law sits inactive on the books.  It will likely be overturned before it ever sees action.

At the moment, online casinos and online gambling make up a $23 billion a year industry.  A good deal of that money comes from gamblers in the United States as the United State remains the biggest market for online casinos regardless of their legal standing in the country.  Not all, but some online casinos have made it very easy for online gamblers to make wagers at their sites by providing payment methods that circumvent the use of traditional bank accounts and credit cards. 

When online casinos are finally regulated in the United States, the industry will only explode and continue to make billions more while Americans come to trust them as legitimate gambling venues.