> The random-effects meta-analysis revealed a significant positive effect of neuromodulation techniques on reducing stuttering severity and frequency. Meta-regression showed that transcranial direct current stimulation (tDCS) had the most significant effect in reducing stuttering severity and frequency among standalone interventions. Combined therapy approaches, which paired NIBS with speech therapy, resulted in the most substantial improvements overall. Sensitivity analyses confirmed the robustness of the results despite minor heterogeneity across studies.