Background <p>Stroke often leads to spasticity, complicating motor function recovery. Surface Electrical stimulation (ES) and intramuscular electrical stimulation (IMES) are promising interventions for modulating spasticity in stroke-affected muscles.</p> Aims <p>This study evaluated and compared the immediate effects of surface ES and IMES on spasticity in stroke survivors, focusing on the tibialis anterior muscle and its effects on the Gastrocnemius and Soleus muscles.</p> Methods <p>Sixty stroke survivors were randomly assigned to either the surface ES or IMES groups. Each intervention was applied for 30&#xa0;min. Spasticity was assessed using the Modified Ashworth Scale (MAS) and H-reflex parameters, including maximum latency, H-amplitude, M-amplitude, and the H/M ratio, measured before and after a single intervention session. Electromyographic data were analyzed to capture changes in spasticity markers, and effect sizes were calculated to evaluate within-group changes and between-group differences. Statistical analysis was conducted using MANOVA.</p> Results <p>Both surface ES and IMES groups showed significant improvements in MAS scores and increased H-reflex latency in the Gastrocnemius and Soleus muscles (<i>P</i> = 0.02, effect size = 0.34). The IMES group uniquely reduced H-amplitude in the Gastrocnemius muscle with small effect size = 0.26. No significant differences were found between the groups across spasticity measures (<i>P</i> &gt; 0.05).</p> Conclusion <p>Surface ES and IMES effectively reduce post-stroke spasticity, with IMES showing additional neurophysiological benefits in the Gastrocnemius muscle. Both techniques are viable for immediate spasticity reduction, though further research is needed to explore long-term effects and underlying mechanisms.</p> Clinical trial registry number <p>Pan African clinical trial registry (PACTR202101475345034) /Date of Approval: 28 Jan 2021.</p>