Azpeitia is home to approximately 14,000 residents, making it a small but vibrant town. The majority of the population identifies as Basque, and the Basque language, Euskara, is widely spoken alongside Spanish. The town has a slightly aging population, like much of rural Spain, but it has also seen some population growth in recent years due to the local industrial economy and the attractiveness of the area for tourists and second-home buyers.
The town has a strong sense of community, with many residents participating in local festivals, sports, and cultural activities. The demographic mix reflects the traditional Basque way of life, but there is also a growing diversity of residents as more people move into the region from other parts of Spain and Europe.