What Flat Files Are
Flat files are spreadsheet templates that let you create or update multiple Amazon listings simultaneously. Instead of editing each listing individually through Seller Central's interface, you fill in a spreadsheet with all your product information and upload it in one go. For sellers with large catalogues or frequent updates, flat files save enormous amounts of time.
When to Use Flat Files
Flat files make sense when you need to create many new listings at once, update prices or quantities across your entire catalogue, add or change backend keywords for multiple products, modify product details like bullet points or descriptions in bulk, or migrate listings from one template format to another. Any task that would require repetitive clicking through Seller Central for dozens of products is better handled through flat files.
Getting the Right Template
Download the inventory file template for your product category from Seller Central (under "Add Products" then "Upload a spreadsheet"). Each category has its own template with category-specific fields. Use the correct template for your products — uploading the wrong category template will cause errors. The template includes a "Valid Values" tab explaining what each field requires.
Key Fields
Required fields typically include SKU, product identifier (EAN or UPC), product name, price, quantity, condition, and category-specific attributes. Optional but important fields include bullet points, description, search terms, and images. The "Update Delete" field tells Amazon what to do with each row — use "Update" to modify existing listings or "PartialUpdate" to change specific fields without affecting others.
Common Errors and Solutions
The most common errors are formatting issues — cells formatted as numbers when Amazon expects text (particularly for barcodes), incorrect date formats, and special characters that break the upload. Save your file in the correct format (tab-delimited text) and check the processing report after upload for errors. Amazon's error messages can be cryptic but usually indicate which field on which row has the problem.
Best Practices
Always download your current listings first as a backup before making bulk changes. Make changes to a copy rather than the original. Upload changes in small batches initially to verify they work correctly before processing your entire catalogue. Keep a master spreadsheet of your listings that you can reference and update over time.
Flat files have a learning curve, but once mastered they become one of the most powerful tools for managing a large Amazon catalogue efficiently.