Reporting Gambling Winnings (and Losses) on Tax Returns
Gambling winnings are income, the same as money you make from your job or from renting out half of your two-family house. Gambling winnings are just as much income as other somewhat "speculative" earnings you may have, such as commissions on sales (since that's not guaranteed but depends on making the sales) or a holiday bonus (which depends on whether and how much your employer wants to give you). As such, it is taxable as any other income.
Income: The IRS has made this very plain: in their online advice under "Tax Topics: Topic 419, Gambling Income and Loses", the IRS said in no uncertain words that " Gambling winnings are fully taxable and you must report the income on your tax return." (The IRS also provides an interactive online 10-minute interview for gamblers; the online assistant takes you through a series of questions and provides responses that leads you to answers in claiming your gambling winnings (and deduct your losses).
Sometimes the payer (the one paying your winnings; e.g. the casino) must issue you a form (Form W-2G) with your winnings and any withholding for your taxes--this is typically if your winnings reach certain levels, which vary by type of gambling. (The last instructions page of the Form W-2G lists threshold amounts of winnings requiring that the form be issued to you.) But even if you do not get a form, you do not get a free pass--you still need to legally report winnings topping over $600. As the IRS goes on to say on this subject: "A payer is required to issue you a Form W-2G.pdf, Certain Gambling Winnings, if you receive certain gambling winnings or have any gambling winnings subject to federal income tax withholding. You must report all gambling winnings on your Form 1040 as 'Other Income' (line 21), including winnings that aren't reported on a Form W-2G.pdf. When you have gambling winnings, you may be required to pay an estimated tax on that additional income. For information on withholding on gambling winnings, refer to Publication 505, Tax Withholding and Estimated Tax."
Can I Deduct Losses: You can deduct your gambling losses if you itemize your tax returns on a Form 1040 Schedule A. You have to track all your losses and winnings and report them comprehensively, and you can only deduct up to the amount of gambling income you report. That is, you can use your gambling losses to offset your winnings for tax purposes, but you can't do more than offset your gambling income: gambling losses cannot be deducted from or be offset against other forms of income.
Unfortunately, the 2017 Tax Cuts and Jobs Act while enhancing the standard deduction also reduces certain itemized deductions, so the net effect is to make itemizing less attractive for many people—they end up doing better without itemizing. That being the case, whether it is worthwhile to try to itemize and deduct your gambling losses is unclear--but is clear is that you must report (and pay taxes on!) your winnings.
If you are a full-fledged, professional gambler who depends on gambling winnings as a livelihood to pay bills and put bread on the table, you report winnings (and expenses, such as meals, lodging, transportation, food) on Schedule C, Form 1040. The IRS more than likely will ask you to prove that gambling is your full-time, actual occupation, under a 1987 US Supreme Court decision establishing the professional gambler standard.
Income from cryptocurrency
Suppose you "gamble" by trading cyptocurrency--is any profit you make taxable? Yes, but not under the gambling taxation rules discussed above. Instead, trading in cryptocurrency, where you make money (hopefully!) by buying low and selling high (so exchanging, say, dollars for Bitcoins when Bitcoins are worth X, then trading the Bitcoins for dollars later, after the value of Bitcoins has risen and they are now worth X plus) is considered the equivalent of trading in any other commodities, such as gold or oil. The income you make is taxed like the income from any other commodities trading.
Taxing rules from Fantasy sports
Not a fantasy—whether it is one day or season long, you have to track your winnings and report to Uncle Sam when they top $600 or more. If you receive over $20,000, and are paid through PayPal, you will receive a Form 1099-K.
Season-long fantasy sports is not considered gambling, so any income there is taxed like income from any other "job" you have. The treatment of daily fantasy sports (DFS) varies by state in terms of whether it is legal or not, and whether it is considered gambling or not. While you should check with your own tax preparer or accountant for how to report DFS income, it is a given that the income will be taxable and you will need to report it and pay taxes on it.
Then there are the State individual taxes
Your state may also want its share of your gambling income. There is no uniformity of how a tax taxes gambling winnings (or will allow casual gamblers to deduct associated losses). Some do, some don’t. This is not surprising as states are tussling with what types of games constitute gambling and whether it is a legal activity in the first place.
If you are unsure how to report income accurately, check with your tax accountant or call your state taxing department for help. As with all state income tax issues, this is a question which must be answered state-by-state.
Taxation of gambling businesses
If you happen to be licensed by a state to provide gambling services--that is, to run a gambling business--for you, gambling is not "gambling". It’s your business. Income or profit from your operations will be treated like any other business income.