Many of the casinos across the country are now requiring this type of information, and it is usually because the state gaming commissions are requesting that it be kept on file. But no, if you have future winnings later in the year, they will not combine all of these and end up sending you a form that you must report your winnings. As far as proving what you spent on your gambling losses, the best way to do this is ask the casino to provide you with a loss statement. If you use a players card each time you gamble, they will have a record of everything you have spent. You can also keep your own manual records which could be verified by bank withdrawals or credit card advances.
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