The IRS allows you to claim your gambling losses as a deduction, as long as you don’t claim more than you won.
The deduction can only be claimed if you choose to file Schedule A, Itemized Deductions. You should also have receipts, tickets, statements and documentation such as a diary or similar record of your losses and winnings to support your deduction claim.
If you won money and lost money, you have to report those amounts separately—winnings are reported as “Other Income” on Form 1040, and losses are reported as a deduction on Schedule A. You can’t simply subtract your losses from your winnings and report what’s left over. Even your records—which you should keep as proof of your gambling outcomes—should show your winnings separately from your losses.