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Objective: The generally good prognosis of low‐ and intermediate‐risk differentiated thyroid cancer (DTC) underscored the need to identify those few patients who relapse. Design: Records of 299 low‐ or intermediate‐risk DTC patients (mean follow‐up 8.2 ± 6.2 years) were retrospectively reviewed. The sample was classified following the American Thyroid Association (ATA) dynamic risk stratification (DRS) system. Patients and Measurement: After classifying patients according to DRS at the first visit following initial therapy (FU1), structural recurrence occurred in 2/181 (1.1%), 5/81 (6.2%) and 13/26 (50.0%) with excellent, indeterminate and biochemical incomplete response to treatment, respectively. All relapses but one happened within 5 years from FU1. Univariate analysis comparing excellent, indeterminate and biochemical incomplete with structural incomplete responses at the end of the follow‐up, identified tumour size (p <.001), T status (<0.001), positive lymph nodes (N) (p <.01), multifocality (p <.004), need of additional radioactive iodine (RAI) (p <.0001) and first DRS status (p <.0003) as risk factors of recurrence. In the multivariate analysis, only RAI remained statistically significant (p <.02). Comparison between excellent and indeterminate with biochemical and structural incomplete responses, identified tumour size (p <.0004), T (p <.01), N (p <.0001), bilaterality (p <.03), first DRS status (p <.0001) and RAI (p <.001) as recurrence risk factors. T (p <.01) and first DRS (p <.0006) were confirmed in the multivariate analysis. Conclusions: Patients with DTC classified as low‐ or intermediate‐risk of recurrence with excellent response to treatment at FU1 rarely develop structural disease and this occurs almost exclusively in the first 5 years. Initial DRS status is an accurate tool for determining the risk of recurrence. [ABSTRACT FROM AUTHOR]