The geographic zone from which a location derives a defined percentage (commonly 70-80%) of its customer visits, modeled using observed mobility patterns.
The 70–80% threshold is a convention, not a hard rule, but it’s what makes a trade area meaningfully different from a simple radius or administrative boundary it’s shaped entirely by where people actually come from, so it might stretch far along a highway corridor and barely cross a river half a mile away.
Further reading: Trade area analysis · Retail site selection
