Internet trust in Spain: Longitudinal evidence on socio-economic and digital adoption behavior

Using the 2014 - 2021 waves of Spain's ICT-H household panel, we track Internet trust for 59,648 users across 130,013 person-year observations. Employing a correlated random-effects ordered-probit model, we find that improvements in digital skills and first-hand use of transactional services are the strongest predictors of higher reported trust, while traditional socio-economic markers show comparatively weaker associations. Once skill levels are controlled, age differences largely vanish; however, women still report lower trust, and the pandemic years register a notable dip, pointing to attitudinal and systemic factors that skill policies alone cannot address. The findings suggest the need for advanced skill training, guided initial transactions, and robust consumer safeguards, particularly for women and low-income users, as plausible components of a trust-oriented digital-inclusion strategy. More broadly, the results contribute to the EU digital trust agenda by underscoring that expanding digital participation must be accompanied by policies that strengthen user confidence and online security.