Consumer Online Shopping Adoption and Small and Medium-Sized Enterprises’ E-Sales Participation in the European Union: A Longitudinal Alignment Analysis, 2015–2024

Buying online has become ordinary behaviour for European consumers, yet selling online remains a minority practice among small and medium-sized enterprises (SMEs). This study asks whether the two have developed in step within countries. Using Eurostat household and enterprise ICT survey data for the EU-27 from 2015 to 2024 (268 complete country-years), we measure their alignment as a within-year standardised difference. The measure captures relative cross-country positioning between two adoption indicators; it does not quantify unmet demand or transaction volumes. Cross-country dispersion in consumer adoption fell steeply and significantly (SD trend −0.91 per year, R2 = 0.96; country-clustered bootstrap 95% CI [−1.25, −0.51]), while dispersion in SME participation drifted upward only slightly and not significantly, and the annual correlation between the two edged down from 0.539 to 0.415 without reaching significance under the same bootstrap. SME-leading and consumer-leading observations retained their category in roughly 90% of year-to-year transitions (Cohen’s κ = 0.74), whereas the aligned category showed lower retention. Consistent with this, the within-country association between the two series is small and statistically non-significant in both the two-way fixed-effects specification (β = 0.116, p = 0.112, N = 268) and the first-difference specification (β = 0.091, p = 0.055, N = 239), and it remains weak across nine robustness specifications and under wild cluster bootstrap and equivalence testing. It is, however, stronger when member states are weighted by economic size; this changes the estimand and does not establish heterogeneity by economy size. Consumer adoption is therefore an incomplete indicator of national e-commerce development, and the two dimensions warrant separate monitoring.