Background: Rapid severity assessment at emergency department (ED) entry guides imaging priority and time-critical care in suspected stroke. Objective: To compare the National Institutes of Health Stroke Scale (NIHSS) and the Scandinavian Stroke Scale (SSS) for identifying clinically significant stroke at ED arrival, using non-contrast CT (NCCT) as reference. Methods: Cross-sectional study at a tertiary ED (January 2024–January 2025). Adults with suspected ischemic stroke were scored with NIHSS and SSS at presentation prior to NCCT. We summarized severity distributions, inter-scale agreement (κ), and diagnostic performance versus CT for moderate–severe involvement in the CT-classifiable subset. Results: Among 306 patients, NIHSS categorized 39.5% mild, 40.5% moderate, 19.9% severe; SSS yielded 38.2%, 40.8%, 20.9%, respectively. Agreement across three categories was moderate (κ=0.567). In the CT-classifiable subset (n=13), SSS showed higher sensitivity than NIHSS (62.5% vs 37.5%) at identical specificity (80.0% each). PPV favoured SSS (83.3% vs 75.0%) and NPV was 57.1% vs 44.4%, respectively. Conclusions: For early ED triage, SSS demonstrated higher sensitivity than NIHSS for CT-defined moderate–severe involvement while maintaining similar specificity, supporting SSS as a practical, sensitive bedside option.