Supplier Shipped Wrong Parts or Failed Inspection? Here's What to Do

What this looks like

It is 10:18 Wednesday morning. Receiving signed for PO 7184 yesterday afternoon, 320 machined brackets for the gearbox subassembly that runs Friday. Incoming inspection pulled the standard sample of 30 units this morning. The QC tech just walked over with a gauge report. Of the 30 sampled, 22 are out of tolerance on the bore diameter, ranging from 0.0015 to 0.004 oversize against a 0.001 bilateral tolerance. The drawing revision in their packing slip matches the PO. The parts do not match the print. The inspector flagged the lot and is asking what you want to do with the rest of the carton.

A quality issue on shipment can take three different shapes and each one calls for a different containment plan. The simplest case is a clean miss against a clear spec, where the supplier ran the part wrong, the gauge agrees, the print is unambiguous, and the supplier is going to own the issue once they see the inspection record. The second case is a spec interpretation gap, where the print could be read two ways and the supplier ran their interpretation, which is technically defensible from their side. The third case is a creeping process problem, where the supplier passed initial samples but is drifting on production runs, often because of tooling wear or a process change they did not surface. The conversation, the documentation requirement, and the long-term action are different in each.

Before you contact the supplier, run the diagnostic. Pull the print and the PO acknowledgment and confirm the spec is unambiguous. Get the inspection record from quality with the actual measurements, the gauge calibration record, and the inspector's sign-off. Check whether this is the first time this part has come back from this supplier with a quality issue or whether there is a pattern. Confirm with quality whether the rejected lot can be sorted (some parts, some lots, some of the time) or whether it is a full reject. If you can sort, you may be able to release a portion of the shipment to production and run the gap on a smaller balance. If you cannot sort, the entire receipt needs to ship back or be scrapped on site, and the replacement quantity is the full PO.

Why it matters

The financial picture is large and lands across multiple lines. The original PO cost on a $48 machined bracket times 320 units is $15,360 of inventory you cannot use. If the line that consumes the brackets idles waiting for replacement, you are adding $10,000 per hour of line-down cost on top of the part cost. The supplier's replacement freight, possibly air freight on the recovery, is another $3,000 to $40,000 depending on weight and origin, and the chargeback math determines whether you or the supplier carries it. If the supplier disputes the chargeback later (and they will if your documentation is loose), the liability question can sit unresolved for months and surface as a credit memo dispute on the next quarterly close.

On the operational side, the cascade is faster than buyers expect. Production planning has to decide whether to reallocate the Friday cell to a different build, which means the planner needs the rejection news inside an hour of the inspection report, not at the end of the day. Quality has to decide whether the issue is contained to this lot or warrants an NCR (nonconformance report) that triggers an audit of recent shipments from the same supplier. The customer-facing build that depends on the gearbox subassembly may need a schedule notification if the replacement runway is more than a few days. Each one of those conversations needs the same set of facts (rejection rate, root cause if known, replacement plan, cost) and you are the source.

The AP exposure is the one buyers most often miss. The supplier will invoice on the receipt, since the parts technically shipped and were received. If AP processes the invoice on the standard three-way match before quality flags the rejection, you have paid for inventory you cannot use. Recovering the payment after the fact means a credit memo conversation with the supplier, and credit memos on rejected shipments routinely take six to ten weeks to land. Block the invoice on the same day the rejection is logged, with a note to AP referencing the inspection record. The two minutes you spend on that note prevent a month of AP cleanup.

What to do, step by step

Step 1: Contain the bad inventory the moment quality flags it. Get a hold tag on the entire lot. Make sure receiving knows the parts cannot be moved to the line. If your ERP supports a quality-hold status on the PO line, post it the same hour the inspection report lands. Containment is the first move because every minute the parts are loose is a minute they could be pulled to the line by someone who has not heard about the rejection yet.

Step 2: Document the rejection in writing with the actual measurements, the gauge calibration record, and the inspector's sign-off. The documentation is the foundation of the chargeback later, the NCR if one is opened, and the conversation with the supplier today. Photos of the bad parts next to a known-good reference, with the gauge readings visible, are worth the five minutes to capture and they prevent the supplier from later disputing what was actually rejected.

Step 3: Contact the supplier the same day with the rejection record attached. Lead with the facts (lot, quantity rejected, measurements, the spec they violate) rather than frustration. The supplier is going to have to take this back to their production team, and a clear factual report gets a faster recovery plan than an angry email.

Initial supplier follow-up template: "[SUPPLIER NAME], we received PO [NUMBER] for [PART DESCRIPTION] on [DATE] and incoming inspection rejected [X] of [Y] units sampled from the lot. Measurements attached, gauge calibration record attached. The rejection is [SPECIFIC SPEC VIOLATION] against the print on revision [REV LEVEL] referenced on the PO. Production is impacted starting [DATE]. We need (1) a replacement-shipment plan with a firm ship date by end of business [DAY], (2) your view on root cause within 48 hours, and (3) confirmation of freight terms on the replacement and disposition of the rejected lot (return at your cost or scrap on site with credit memo). Please respond by [TIME, DAY]. [YOUR NAME]"

Step 4: Decide whether to open an NCR (nonconformance report). The threshold is your team's SOP. Most teams open an NCR for any rejection that triggers a replacement shipment, any rejection above a percentage threshold of the lot, or any rejection on a critical-to-quality characteristic. The NCR creates the formal record that drives a corrective action request to the supplier and triggers the audit on recent shipments. If quality is opening the NCR, your job is to give them the supplier-side detail (root cause when you have it, the replacement plan, the freight disposition).

Step 5: Block the AP invoice the same day the rejection is logged. A two-line note to AP with the PO number, the inspection record, and an explicit "do not approve invoice on the rejected quantity" prevents an overpayment that takes weeks to recover after the fact.

AP note template: "[AP CONTACT NAME], heads-up on PO [NUMBER]. Incoming inspection rejected [X] of [Y] units against the print spec. Inspection record attached. Replacement shipment is pending from the supplier. Please block invoice processing on this PO until the replacement is received and approved, or until a credit memo from the supplier covers the rejected quantity. I will update you when either lands. [YOUR NAME]"

Step 6: Communicate internally before production has to ask. Quality, the planner, the line lead, and your manager all need a version of the news within the same hour. Two sentences each, all sent the day the rejection lands.

Internal update template: "[PLANNER NAME], quality rejection on PO [NUMBER] for [PART DESCRIPTION]. [X] of [Y] units rejected by incoming inspection on [SPECIFIC SPEC]. Lot is on hold. Working a replacement plan with [SUPPLIER NAME] today. Best-case replacement ETA [DATE]. Friday gearbox build will need a backup plan or a schedule shift. I will confirm a replacement ship date and freight terms by [TIME, DAY]. NCR pending decision with quality. [YOUR NAME]"

How PO-Relay handles this

When a quality hold is posted on a PO line in your ERP, PO-Relay's task board flags the loop as "quality hold" and surfaces the rejected quantity on the Parts Dashboard sorted to the top by urgency. The supplier's prior shipment notice, the original PO acknowledgment, and any historical quality flags on the same supplier are pulled into the task context, so you start the supplier conversation with the full pattern visible rather than treating it as a one-time miss.

Email Intelligence watches the supplier reply on the rejection thread for a replacement plan, a root-cause statement, and a credit memo or freight disposition. When the supplier responds, the assistant tags the email against the right PO, extracts the proposed replacement ship date, and updates the task. If the reply is vague or missing one of the three required elements, the loop stays flagged as "awaiting replacement plan" until a complete response lands.

Auto Follow-Ups drafts the rejection email, the AP-block note, and the internal update pre-loaded with the PO number, part description, rejected quantity, the specific spec violation, and the inspection record reference. The escalation language for second-attempt follow-ups is layered in if the supplier does not respond inside the deadline. You review every draft, attach the actual inspection PDFs, and send from your own inbox. PO-Relay never sends email and never writes to your ERP.

The Morning Report resurfaces the open quality hold every day until the replacement is received and approved or the loop is closed with a credit memo. The afternoon recap captures movement on the supplier conversation, the AP block status, and any NCR progress so the audit trail stays intact for the supplier-quality review later.

Common mistakes to avoid

• Skipping the containment step. If the rejected lot is not on hold the moment quality flags it, the parts can be pulled to the line by someone who has not heard about the rejection yet, which turns a documentation problem into a customer-facing quality escape. The first move on any rejection is the hold tag and the ERP quality-hold status. Everything else (the supplier conversation, the AP note, the internal update) comes after containment.
• Sending an angry email to the supplier instead of a factual one. The supplier is going to take whatever you write back to their production team. A clear factual record (lot, quantity, measurements, spec violation, inspection sign-off) gets a faster recovery plan than an emotional complaint, because the supplier's team can act on the facts. The frustration is real and legitimate, but it should land in the negotiation on chargebacks, not in the first rejection email.
• Not blocking the AP invoice the same day. The supplier will invoice on the receipt, since the parts shipped and were received. If AP processes the invoice before quality flags the rejection, you have paid for inventory you cannot use. Credit memo recovery routinely takes six to ten weeks. Block the invoice the day the rejection is logged, with a note referencing the inspection record. Two minutes today prevents a month of AP cleanup.
• Treating every rejection as a one-time miss. If a supplier has rejected on quality before, the second rejection is a pattern, not an incident. Pull the historical record on every rejection. Three rejections in a quarter on the same characteristic is a process problem on the supplier side and the right response is a corrective action request, possibly an audit, and a sourcing review. Treating each one as the first time you have seen the problem leaves the underlying issue unfixed.

Keep reading

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• Partial shipment from a supplier →
• Shipped but not received →
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