Prioritize order accuracy, on-time shipping rate, dock turn times, throughput per labor hour, and cost-per-order. Verify infrastructure: dock doors, pallet positions, racking, temperature control, IT integrations (WMS/APIs), and contingency capacity for peak volumes. Evaluate SLA penalties and performance reporting cadence.

Assess the 3PL’s carrier roster, daily pickup frequency, and negotiated parcel/LTL rates. Model transit-time reductions to core customer ZIP clusters and quantify landed cost savings. Confirm intermodal links and proximity to major routes to support consistent transit windows and reduced expedited shipments.

Compare fixed vs variable fees: receiving, storage (per pallet/ft2), picking (per line/sku), packing, returns processing, and monthly minimums. Review billing granularity, chargeback policies, minimum service levels, liability limits, and exit terms to avoid hidden cost escalation as volume changes.

Require a modern WMS that supports API-based integrations, real-time inventory visibility, EDI or REST connectivity, and standardized reporting. Confirm support for order orchestration, batch processing, ASN generation, and access to performance dashboards to monitor SLA adherence and inventory health.