DC sales tax is an important part of shopping and business transactions in Washington, DC. Understanding the applicable sales tax rate helps consumers calculate the total cost of their purchases and allows businesses to maintain accurate records and follow local tax rules.
this resource:https://lawsenior.com/dc-sales-tax/

I'd like to add some for Oregon as well. The closest ones default to Washington state and California, and that means (among other things) that placing online orders default to charging sales tax until I override it. (There is no sales tax in Oregon.).