Costco deduction codes — triggers, evidence, windows.

What triggers it

Costco depot or warehouse received fewer cases than the invoice declared. Common on mixed pallets and floor-loaded trailers.

Evidence to dispute

Packing list, BOL, weighed shipment record, trailer seal log, and depot receiving record.

Filing window

60 days from chargeback date in Supplier Portal

Typical success rate

60–75% when shipment was palletized and weighed

Root-cause fix

Move from floor-load to palletized; weigh every outbound trailer; reconcile packing-list to BOL.

Source: Costco Vendor Compliance — Receiving Standards

What triggers it

Club-pack configuration did not match Costco's specification — wrong unit count per pack, missing IRC, missing item-level UPC, or shrink-wrap failure.

Evidence to dispute

Costco-approved spec sheet, photos of finished club pack, and pack-out QA record.

Filing window

60 days from chargeback date

Typical success rate

30–45% — often valid; wins are scope or spec-version disputes

Root-cause fix

Lock club-pack spec with Costco buyer in writing; QA finished packs against spec at random intervals; rotate QA samples weekly.

Source: Costco Vendor Packaging & Labeling Guide

What triggers it

Trailer arrived outside the booked appointment window or routed through wrong depot. Costco depots run tight dock schedules.

Evidence to dispute

Appointment confirmation, carrier GPS/ELD record, depot arrival timestamp, and any depot-acknowledged exception.

Filing window

60 days from chargeback date

Typical success rate

45–60% — depot-acknowledged exceptions win

Root-cause fix

Book appointments earlier in the window; pre-stage trailers near high-volume depots; never miss an appointment without rescheduling.

Source: Costco Vendor Compliance — Routing & Delivery

What triggers it

Invoice price did not match the cost on the PO or the negotiated promo. Common during quarterly cost reviews.

Evidence to dispute

Original PO, signed cost agreement or buyer email confirming new cost, and the matching invoice.

Filing window

60 days from deduction date

Typical success rate

75–90% when cost agreement is documented

Root-cause fix

Capture every cost change in writing from buyer; reconcile invoice cost to agreement weekly.

Source: Costco Vendor Pricing process

What triggers it

Third-party audit firm flagged a duplicate payment, missed allowance, or pricing error from prior periods. Often arrives 12–36 months later.

Evidence to dispute

Original PO, original invoice, original remittance, and bank reconciliation when payment is contested.

Filing window

Typically 90 days to respond from claim date

Typical success rate

50–70% — many are valid; the rest are double-counted deductions

Root-cause fix

Maintain a post-audit response file by year; never pay without checking original remittance.

Source: Costco Post-Audit process; common third-party audit firms