Overview

Amazon sellers encounter error 18014 when a feed that contains order‑adjustment data lists a negative amount for shipping‑price adjustments. The feed is rejected, preventing the refund from being issued and potentially delaying the buyer’s reimbursement. Understanding why Amazon rejects negative shipping values and how to correct them is essential for anyone who processes refunds in bulk through XML or flat‑file feeds.

Key Points

• Positive numbers only — Amazon expects every refund‑related field, including shipping‑price adjustments, to be entered as a positive figure that represents the amount to be returned to the buyer.
• Applies to XML and flat files — The error can arise whether you upload an XML adjustment feed or a tab‑delimited flat file; the underlying rule about sign‑direction is the same for both formats.
• No credit‑card recharges via feeds — Sellers cannot charge a buyer’s credit card by submitting a negative adjustment; Amazon’s system only processes refunds, not additional fees.
• Simple resubmit fixes the issue — Re‑uploading the same feed with the shipping‑price value changed to a positive number clears the error and allows the refund to proceed.
• Automation scripts must be vetted — Any custom code that builds adjustment feeds should include a validation step to prevent accidental insertion of negative values.

How the Error Occurs

1. Feed parsing detects a negative shipping entry — When Amazon’s feed processor reads the adjustment file, it scans the shipping‑price‑adj field. If the field contains “‑5.00” (or any negative figure), the system flags error 18014.
2. XML example — An XML snippet such as <ShippingPriceAdjustment>-3.99</ShippingPriceAdjustment> triggers the same rejection because the value is not a positive decimal.
3. Flat‑file example — In a tab‑delimited file, a line like 1234567890\t-2.50\t... where the second column represents the shipping adjustment will also cause the error.