27 C.F.R. § 19.245

(a) The distilled spirits tax. Sections 5001 and 7652 of the IRC impose a tax on all distilled spirits produced in, or imported into, or brought into the United States at the rate prescribed in section 5001 of the IRC.

(b) Tax credits. Section 5010 of the IRC provides a credit for the wine and flavors content in distilled spirits products. These credits effectively reduce the rate of excise tax paid on distilled spirits products that contain eligible wines and eligible flavors. As a result, the alcohol derived from eligible wine is taxed at the rates specified for wine in 26 U.S.C. 5041, and the alcohol derived from eligible flavors is not taxed to the extent that it does not exceed 2.5 percent of the alcohol in the product. This results in an effective tax rate on the distilled spirits product that is lower than the rate prescribed in 26 U.S.C. 5001.

(c) Eligible wine and eligible flavor. The credit for the wine and flavor content of a distilled spirits product is allowable only if the wine or flavor contained in the product is an “eligible wine” or an “eligible flavor”. To determine whether a wine or flavor is eligible, refer to the definitions in § 19.1 and 26 U.S.C. 5010.

(d) Application of effective tax rates. Section 19.246 describes how the proprietor should compute the effective tax rate for each distilled spirits product containing eligible wine or eligible flavor. Sections 19.247 through 19.250 set forth several different methods that the proprietor may use in applying the effective tax rates to taxable removals of products from the proprietor's bonded premises.