How are demurrage and detention calculated, and how do I avoid them?

**Definitions:** - **Demurrage** - Daily charge by the port/terminal once free storage time inside the terminal expires. Free time is usually 3-7 days from container discharge. - **Detention** - Daily charge by the shipping line once free time for using the empty container outside the terminal expires. Free time is usually 7-14 days from gate-out. - **Combined "demurrage + detention" (D&D)** - Some carriers quote a single combined free time of 10-21 days. **Typical daily rates** (per 20ft container, indicative, varies sharply by port and carrier): - Lagos / Apapa: USD 60-150/day demurrage; USD 40-100/day detention - notoriously expensive - Durban: USD 30-80/day combined - Mombasa: USD 40-100/day combined - Tema: USD 50-120/day combined - Jebel Ali: USD 30-70/day combined Rates escalate after the first 5-10 days (sometimes doubling or tripling). **Most common causes:** 1. Import documents not ready when the vessel arrives (missing pre-shipment certificate, wrong HS code, missing Form M/IDF) 2. Delayed payment of import duties 3. Inspection holds for regulated goods (steel, electrical) 4. Truck shortages at peak season 5. Port congestion (especially Apapa, Tema, Mombasa during rainy season) **How to avoid them:** - File the import licence / pre-shipment certificate **before** the goods ship from China - Use a freight forwarder who tracks vessel ETA and pre-positions documents - Pay duty within 48 hours of assessment - Negotiate longer free time at booking - many carriers will extend to 14-21 days combined on request, especially for repeat shippers - Use a single consolidated B/L instead of several small ones - For Nigeria specifically: budget for and plan around the typical 7-14 day extra clearance delay at Apapa