Tolosa has a population of approximately 18,000 residents, making it a small yet vibrant city. The majority of the population is of Basque origin, and both Spanish and the Basque language (Euskara) are widely spoken. The city has a relatively young demographic, with a mix of families, professionals, and students, contributing to its lively atmosphere.
Tolosa’s population has seen modest growth over the years, largely due to its appeal as a commuter city for those working in nearby San Sebastián. The city also attracts a diverse range of visitors, from international tourists to those attending cultural festivals and events.