Overview

Error 90056 is a feed processing error that Amazon Seller Central returns when a product listing feed submission is missing a value in one or more required columns. This is one of the most common feed errors sellers encounter when uploading or updating product listings via flat files, inventory loaders, or API-based feed submissions. Understanding how to diagnose and resolve this error quickly can prevent delays in getting your products listed and available for sale.

Key Points / What Sellers Need to Know

• What triggers it — Error 90056 fires when your feed file contains a row that is missing data in a column Amazon considers mandatory for that product type.
• Where it appears — You will typically see this error in your feed processing reports, which can be downloaded from the Inventory section of Seller Central or retrieved via the Selling Partner API.
• Common culprits — Required fields vary by product category, but frequently missed columns include SKU, product title, price, quantity, condition, and product identifier (UPC, EAN, or ASIN).
• Quick fix — Identify the specific column referenced in the error message, populate the missing value in your file, and resubmit the feed.

How This Error Occurs

When you submit a product feed to Amazon — whether through a flat file upload in Seller Central, a third-party listing tool, or an API integration — Amazon validates every row against the required fields for the relevant product category. If any row is missing a value in a required column, the system rejects that specific row and logs Error 90056 in the processing report. The error message will typically indicate which column is missing a value, though in some cases sellers may need to cross-reference their file against the category-specific flat file template to identify the gap. It is important to note that a single feed submission can generate multiple instances of this error if several rows are missing data.

How to Fix It

Start by downloading the feed processing report from Seller Central under the "Monitor Upload Status" section. The report will list each SKU that triggered Error 90056 along with the column name that is missing a value. Open your original feed file, locate the affected rows, and fill in the required data. Before resubmitting, cross-check your file against Amazon's category-specific flat file template, which you can download from the "Add Products via Upload" page in Seller Central. These templates clearly mark which columns are required versus optional for your product type. Once the missing values are populated, resubmit the corrected feed and monitor the new processing report to confirm the errors are resolved.