D.C. Mun. Regs. tit. 9, § 425
425.1 The sale of or charge for the service of car washing, including cleaning, washing, waxing, polishing, or detailing an automotive vehicle is subject to sales tax.
425.2 The sale of or charge for self-service car washing is not subject to sales tax.
425.3 Persons operating places of business for the purpose of car washing must report and pay the sales tax measured by the gross proceeds derived from these services.
425.4 Materials such as cleaning fluids, wax, and other consumable supplies used in connection with the services of car washing are subject to the sales tax and the tax should be paid by the car wash purchasing such items. If the tax was not paid at the time of purchase of the items, those purchases must be reported to the District and a use tax paid on the amount of the purchases.
SOURCE: Final Rulemaking published at 62 DCR 4890 (April 17, 2015).