Average Resolution Time (ART) is the average elapsed time from when a customer submits a ticket to when their issue is fully resolved, measured across your entire ticket population.

ART captures the customer's experience of time, not just agent effort. A ticket might have 15 minutes of actual handling time but take 3 days to resolve because it sat in queues, waited for approvals, or required information from another team. ART exposes those gaps.

The formula is straightforward: Total time to resolution across all tickets / Number of tickets resolved. But "resolution" needs the same rigor as FCR—exclude tickets that reopen within your lookback window. Most teams measure ART in hours for live channels and days for async channels like email.

ART is most useful when segmented. Your overall ART might be 18 hours, but that average hides a bimodal distribution: simple tickets closing in 2 hours and complex ones taking 4 days. Track ART by complexity tier, product area, and channel. Then attack the outliers. Often, 10% of your ticket types drive 50% of your total resolution time.

Related terms: Average Handling Time (AHT), First Response Time (FRT), First Contact Resolution (FCR)