Subchapter A - Tax on Wagers

26 USC 4401 - Imposition of tax

(a) Wagers 

(1) State authorized wagers 
There shall be imposed on any wager authorized under the law of the State in which accepted an excise tax equal to 0.25 percent of the amount of such wager.
(2) Unauthorized wagers 
There shall be imposed on any wager not described in paragraph (1) an excise tax equal to 2 percent of the amount of such wager.
(b) Amount of wager 
In determining the amount of any wager for the purposes of this subchapter, all charges incident to the placing of such wager shall be included; except that if the taxpayer establishes, in accordance with regulations prescribed by the Secretary, that an amount equal to the tax imposed by this subchapter has been collected as a separate charge from the person placing such wager, the amount so collected shall be excluded.
(c) Persons liable for tax 
Each person who is engaged in the business of accepting wagers shall be liable for and shall pay the tax under this subchapter on all wagers placed with him. Each person who conducts any wagering pool or lottery shall be liable for and shall pay the tax under this subchapter on all wagers placed in such pool or lottery. Any person required to register under section 4412 who receives wagers for or on behalf of another person without having registered under section 4412 the name and place of residence of such other person shall be liable for and shall pay the tax under this subchapter on all such wagers received by him.

26 USC 4402 - Exemptions

No tax shall be imposed by this subchapter
(1) Parimutuels 
On any wager placed with, or on any wager placed in a wagering pool conducted by, a parimutuel wagering enterprise licensed under State law,
(2) Coin-operated devices 
On any wager placed in a coin-operated device (as defined in section 4462 as in effect for years beginning before July 1, 1980), or on any amount paid, in lieu of inserting a coin, token, or similar object, to operate a device described in section 4462 (a)(2) (as so in effect), or
(3) State-conducted lotteries, etc. 
On any wager placed in a sweepstakes, wagering pool, or lottery which is conducted by an agency of a State acting under authority of State law, but only if such wager is placed with the State agency conducting such sweepstakes, wagering pool, or lottery, or with its authorized employees or agents.

26 USC 4403 - Record requirements

Each person liable for tax under this subchapter shall keep a daily record showing the gross amount of all wagers on which he is so liable, in addition to all other records required pursuant to section 6001 (a).

26 USC 4404 - Territorial extent

The tax imposed by this subchapter shall apply only to wagers
(1) accepted in the United States, or
(2) placed by a person who is in the United States
(A) with a person who is a citizen or resident of the United States, or
(B) in a wagering pool or lottery conducted by a person who is a citizen or resident of the United States.

26 USC 4405 - Cross references

For penalties and other administrative provisions applicable to this subchapter, see sections 4421 to 4423, inclusive; and subtitle F.