A pre-shipment inspection (PSI) is a quality check on a finished order, run when production is complete (or nearly complete) and before you release the balance payment. An independent inspector visits the factory, pulls a random sample, and checks it against your specification and approved golden sample.
What the inspector checks
- Quantity: confirms the full order was produced and packed.
- Workmanship and appearance: checks a sample against the golden sample for defects, graded as critical, major, or minor.
- Measurements and function: verifies key dimensions and any functional tests you specified.
- Materials and markings: confirms materials, labels, barcodes, and country-of-origin marking match the spec.
- Packaging: checks retail packaging, inner and master cartons, and carton markings, sometimes with a drop test.
How AQL sampling works
The inspector does not check every unit. They use the ISO 2859-1 (AQL) tables: the lot size sets a sample size, and your chosen AQL level sets how many defects the sample can contain before the lot fails. Common practice is AQL 2.5 for major defects and 4.0 for minor. Agree these numbers with the factory in the RFQ, not after production.
When to book it
Schedule the PSI for when production is at least 80% complete and packed, leaving a few days before the ship date so a re-inspection is possible if the lot fails. If the order is large or the factory is new to you, add a during-production inspection (DUPRO) at 20–60% so problems surface while they are still cheap to fix.
The reason PSI matters is leverage: once you have paid the balance or the container has sailed, a defect is a negotiation. Before that, a failed inspection report is a clear basis to withhold payment until the factory reworks or replaces the goods.