Focus on measurable KPIs: order cycle time, inventory accuracy, on‑time dispatch rate, and cost‑per‑pick. Assess infrastructure (racking, temperature zones), tech stack (WMS, API shipping, EDI), onboarding speed, and value‑added services like kitting and returns processing. Validate carrier mix and transit times to your primary customer zones.

Carrier access affects both freight rates and lead times. Local proximity to intermodal terminals and parcel hubs reduces last‑mile premiums and LTL surcharge exposure. Model zone‑based transit times and carrier mix to quantify the effect on landed cost and fill‑rate obligations for wholesale contracts.

Confirm the provider's experience with customs procedures, bonded storage capability, and import manifesting. Review SLA for customs hold resolution, accuracy of customs documentation, and whether the 3PL offers pre‑pulling or delivery windows that align with carrier cutoffs to minimize detention and demurrage fees.

Prioritize a cloud‑based WMS with real‑time inventory visibility, standard API endpoints for orders and shipping, multichannel order orchestration, and returns management. Check support for barcode scanning, batch/lot tracking, and reporting tools that feed your ERP and BI systems to maintain accurate cost‑to‑serve analytics.

Negotiate seasonal rate structures, guaranteed capacity blocks, and contingency cross‑dock options. Validate the 3PL’s labor flexibility, overtime practices, and access to temporary storage. Include ramp schedules, SLA adjustments, and penalty provisions in contracts to align incentives during peak volumes.