Mendavia is a town and municipality in the province and autonomous community of Navarre, in northern Spain. It lies within the Ebro valley region of Navarre, near the border with the neighbouring autonomous community of La Rioja.
The town is served by the postal code 31587. As a municipality, it covers both the built-up town itself and the surrounding rural territory, a pattern typical of local government organisation throughout Navarre.
Mendavia's position in northern Spain places it within Navarre, one of the country's seventeen autonomous communities and a region historically associated with the Kingdom of Navarre. The municipality sits in the southern part of the province, an area shaped by the Ebro river and its tributaries.