Do you pay sales tax at government auctions?

Usually yes. Sales tax applies to government auction purchases where the item's state requires it, the same as most other sales. The tax is normally based on where the item is located, not where you live.

On GovDeals, for sellers that use its payment service, GovDeals acts as the marketplace facilitator and collects the tax at checkout based on the item's type and advertised location. Some states collect tax on vehicles when you register them at the DMV instead of at checkout. Other platforms and agencies handle it in their own sale terms.

Tax-exempt buyers, such as nonprofits, other public agencies and resellers in some states, can file exemption documents. On GovDeals that should be done before the auction closes. Tax rules vary by state, so check the listing and your state's rules; this is not tax advice.