Cost structure / standard tiers
Congestion translates directly into extended dwell time and a compressed effective free-time window, with downstream demurrage exposure scaling accordingly.
| Condition | Container Dwell Time | Effective Free-Time Impact |
|---|---|---|
| Baseline / uncongested | 2-3 days | Full free-time window (3-4 days) usable |
| Moderate congestion | 4-6 days | Free time often consumed before appointment availability |
| Severe congestion | 5-8+ days | Demurrage risk begins before pickup is logistically possible |
| Vessel queue (ships at anchor/drift) | 0 to 10+ ships | Each added queue-day delays discharge and shifts the free-time clock start |
Once dwell time exceeds the standard free-time allotment, demurrage accrues regardless of whether the delay was caused by terminal congestion rather than the shipper's own scheduling.
Risk mitigation / operational guidance
Monitor leading indicators rather than waiting for dwell-time reports to confirm congestion is already underway: vessel queue counts outside the breakwater, week-over-week changes in average terminal dwell time, and drayage appointment lead times extending beyond their typical baseline. When these indicators rise, prioritize early container pulls within the first 1-2 days of availability rather than waiting until closer to the LFD, since appointment slots tighten quickly as congestion builds. Build extra buffer days into delivery commitments during periods of rising congestion signals, and where carrier routing options exist, consider less-congested gateway terminals for flexible volume. Track dwell time and appointment lead times by terminal rather than by port overall, since congestion severity often varies significantly between terminals operated by different terminal operating companies within the same port.