CSAT (Customer Satisfaction Score) measures satisfaction with a specific touchpoint, typically immediately after the interaction. After a support ticket resolution, after onboarding, after a purchase — the customer rates the experience on a 1–5 or 1–7 scale. CSAT is the most common per-interaction satisfaction metric.
CSAT complements NPS (overall loyalty) and CES (effort). For customer portals, CSAT typically rises after AI customer service is deployed correctly — customers prefer fast, accurate self-service over waiting for human support.