Income tax and gambling losses
Rules concerning income tax and gambling losses vary internationally.
Germany
In Germany, wins are taxable since July 2012 by 5% of the winnings (profit). If for example you placed a bet of 10€ at an odd of 2.00, then your total return (not including the taxes) is 20€, however after the tax deductions, your return will be only 19.50€ (10.00€ x 2.00 = 20.00€ - (5% *10.00€ (your total profit)) = 19.50€).
For online poker, however, because of a hairy legislation, the wins are not taxable yet.
United Kingdom
In the United Kingdom, wins (unless in the course of a trade) are not taxable and losses are not deductible.
United States
In the United States, gambling wins are taxable.
The Internal Revenue Code contains a specific provision regulating income-tax deductions of gambling losses. Under Section 165(d) of the Internal Revenue Code, losses from “wagering transactions” may be deducted to the extent of gains from gambling activities.[1] Essentially, in order to qualify for a deduction of losses from wagering, the taxpayer can only deduct up to the amount of gains he or she accrued from wagering. In Commissioner v. Groetzinger, the Supreme Court Justice Blackmun alludes to Section 165(d) which was a legislative attempt to close the door on suspected abuse of gambling loss deductions.[2]
Wagering Transaction
The Internal Revenue Service has ruled that a “wagering transaction” consists of three elements.[3] First, the transaction must involve a prize. Second, the element of chance must be present. Finally, the taxpayer must give some consideration.
Section 165(d) and Professional Gamblers
In Bathalter v. Commissioner, a full-time horse-race gambler had gains of $91,000 and losses of $87,000.[4] The taxpayer deducted the expenses under Section 162.[5] The service argued that Section 165(d) precluded the taxpayer from engaging in gambling as a "trade or business."[4] The Tax Court held that the taxpayer's gambling was a business activity and allowed the deductions.[6] In essence, the court held that Section 165(d) only applies when a taxpayer is at a loss instead of a net gain and “serves to prevent the [taxpayer] from using that loss to offset other income.” [7] However, if the taxpayer has a net gain, as the horse-race gambler did, then the taxpayer may deduct the expenses under Section 162, and Section 165(d) does not apply.[8]
Section 165(d) and Recreational Gamblers
In addition, in Valenti v. Commissioner, the court reiterated that Section 165(d) applies to professional gamblers as well as recreational gamblers.[9] The court stated, "... it has been held both by this Court and various courts of appeals that wagering losses cannot be deducted, except to the extent of the taxpayer's gains from wagering activities, and it has been so held even where such activities were conducted as a trade or business as opposed to a hobby."[10] Therefore, for example, if a recreational gambler visits a casino one Saturday and accumulates $600 of losses and $200 of gains, that recreational gambler may deduct $200 of the wagering losses (because she can only deduct an amount up to the amount of wagering gains she accrued).