Online commerce presents consumers with a convenient way of shopping outside of
their local jurisdiction, and this online purchase decision is capable of affecting in
significant ways the sales and use tax collections of state governments. However, the
actual revenue impact has proven difficult to estimate. There is considerable work
that examines the revenue impact of seller compliance with sales taxes. However,
there is little work on buyer compliance with use taxes. In this paper, we investigate
the potential impact of cross-border shopping on state use tax liabilities of
buyers, using data from the largest online consumer-to-consumer and business-toconsumer
marketplace, eBay.com. We collect our own data on actual cross-border
shopping transactions from eBay, focusing upon a “representative” commodity
classification and a “typical” day; these data consist of nearly 21,000 eBay listings
generated by roughly 7,000 individual sellers with over 9,000 buyers. These data
allow us to examine the extent of actual, not estimated, cross-border shopping by
buyers, and the subsequent potential impact of this cross-border shopping on state
use tax liabilities. Our results indicate that cross-border shopping is highly prevalent
on eBay, with out-of-state purchases accounting for on average 94 percent of
the volume of a state’s purchase transactions. Even so, given the limited volume
of eBay-based transactions relative to total sales transactions, the likely impact of
cross-border transactions on state use tax revenue streams is quite low, at least at
present, typically less than one percent of actual state sales tax revenues.