CSL1 vs CSL2: what each level means, who pays, and how to get out

What is the difference between CSL1 and CSL2?

Both levels add a redundant, documented inspection on top of your normal controls, and both are paid by the supplier. The difference is who does the checking and how much the OEM trusts the data. Under CSL1 your own people run the extra inspection and certify every shipment. Under CSL2 the OEM has decided your own checks are not enough, so an independent third party runs the inspection alongside CSL1, and its records go to the plant. That independence is the whole point: the SQE wants data that does not depend on the supplier grading its own homework.

How does a supplier end up on CSL1 or CSL2?

The path is almost always the same: a defect reaches the OEM line, the supplier contains it, and then a second escape happens on the same part or process. At that point the SQE stops treating it as an incident and starts treating it as a system problem, which is what Controlled Shipping formalizes. A supplier can also land directly on CSL2 when the escape is severe, safety-related, or when the plant has lost confidence in the supplier's own containment. The best defense is boring: answer alerts inside the first hour and contain before the plant asks, so the second escape never happens.

How do you exit each level, and what does staying cost?

Exit works the same way at both levels: an agreed clean-run window, commonly 20 to 30 production days, a verified 8D with the escape point closed, an updated control plan, and inspection records with zero escapes. At CSL2 those records must come from the independent third party, which is why choosing one that documents well matters as much as choosing one that sorts well. Every extra month on CSL2 means paying inspection labor across shifts while the open order keeps weighing on sourcing reviews. IDS provides third-party CSL1 and CSL2 support at Stellantis Toluca and packages the exit evidence from the first shift; the full exit playbook is in our guide on how to exit CSL2 fast. Under an order right now? Request a quote: plan confirmed within 1 hour.