Overview

Amazon Seller Central allows sellers to manage their product listings in bulk through inventory file uploads, commonly known as flat file templates. This reference page addresses the most frequently asked questions about the upload process, including how long files take to process, what to do when uploads stall, and how to handle common errors. For sellers managing large catalogs, understanding the file upload workflow is essential to keeping inventory accurate and listings up to date.

Key Points / What Sellers Need to Know

• Processing time varies by file size — Small inventory files may complete in just a few minutes, while larger files exceeding 5 MB can take up to eight hours to fully process through Amazon's system.
• There is no way to cancel an in-progress upload — If you need to make corrections, the recommended approach is to resubmit a corrected version of the file, which will overwrite the previous submission.
• Processing reports confirm results — After uploading, sellers should always download and review the processing report to identify which rows succeeded and which generated errors.
• File format matters — Inventory files must follow Amazon's required template format (tab-delimited text) and include all mandatory fields for the product type being uploaded.
• Stuck uploads require support contact — If a file takes significantly longer than the expected processing window, sellers should contact Seller Support for assistance rather than repeatedly resubmitting.

How the Upload Process Works

When a seller uploads an inventory file through Seller Central, the system queues it for processing alongside files from thousands of other sellers. Amazon validates each row of the file against its catalog rules, checking for proper formatting, valid product identifiers, required attribute completeness, and compliance with category-specific requirements. Small files with just a handful of SKUs typically process within minutes because there are fewer rows to validate. Larger files containing thousands of SKUs or those uploaded during peak system activity periods may take considerably longer — up to eight hours in some cases. Once processing is complete, Amazon generates a processing report that details the outcome for every row in the file.