Aim To describe the 2‐year clinical and combined with radiographic caries progression pattern in three cohorts of 2‐(a), 4‐(b), and 6‐yr‐old children (c). Design Baseline sample comprised 600 children (each‐cohort: n = 200). Children's dental surfaces were clinically assessed at schools without air‐drying (epi) in terms of: Clinical (C) caries lesions (d/D) with ICDAS epi‐merged system (C‐ ICDAS epi‐d/D:Sound/Initial‐epi/Moderate/Extensive); fillings (f/F), and missing teeth (m/M). Clinical ICDAS (C) and Radiographic ICDAS (R) indexes were combined (C + R). Caries experience (dmf + DMF ) was expressed as: C‐dmfs + DMFS (Moderate/Extensive‐d/D); C‐ ICDAS epi‐dmfs + DMFS (including Initial‐epi‐d/D); C + R‐dmfs + DMFS ; and C + R‐ ICDAS epi‐dmfs + DMFS . Follow‐up caries progression corresponded to more severe caries score. Results Two‐year follow‐up sample was n = 352 (58.7%‐baseline sample): a: n = 81; b: n = 131; c: n = 140. Around 100% of children presented C + R‐ ICDAS epi‐dmf + DMF ≥ 1, with following C + R‐ ICDAS epi‐dmfs + DMFS means: a: 7.3 ± 14.1; b: 12.2 ± 19.5; c: 13.3 ± 16.9. Progression was about 60% in all cohorts, mainly corresponding, in cohort b and c, to occlusal and distal surfaces of lower first/second‐molar‐primary teeth, and in cohort a to buccal surfaces of upper primary‐incisor teeth. The addition of radiographs increased caries mean and prevalence in 10% as compared to only visual examination. Conclusions Children showed a high C + R caries experience progression rate, mainly related to occlusal and proximal surfaces in lower‐molar teeth and buccal in upper‐incisor teeth.