Amazon Flat File 2026: Bulk Upload Guide for Multiple Products

What Is a Flat File?

A Flat File is an Excel template (.xlsx) provided by Amazon. Each row in the file represents a product or variant. The columns contain all attributes Amazon requires for the relevant category -- from product title to price, bullet points, and images.

Flat Files exist for every Amazon product category. The template for "Electronics" has different columns than the one for "Clothing" because required attributes vary by category.

The major advantage: you can manage hundreds or thousands of products in a single file. Price changes, description updates, or inventory adjustments for your entire catalog can be done in minutes rather than hours.

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When Should You Use Flat Files?

Flat Files are worth using in these situations:

Creating 50+ products: Below that number, manual entry is often faster. Above it, Flat Files are significantly more efficient.
Bulk price updates: When you want to adjust prices on 300 products, you change one column in the file instead of editing 300 individual listings.
Attribute changes: Updating bullet points, titles, or descriptions for many products at once.
Creating variants: Setting up parent-child relationships (colors, sizes) for multiple products in one upload.
Seasonal updates: Quickly adjusting prices and keywords across your entire catalog before Prime Day or Q4.
Catalog migration: When you are moving from another marketplace and want to transfer your catalog to Amazon.

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How to Download a Flat File

Step 1: Choose Your Category

Open Seller Central
Go to Catalog > Add Products
Click "I'm uploading a file to add multiple products"
Select "Download an Inventory File"
Search for the product category your products fall into

Step 2: Configure the Template

Amazon asks which columns you want in the template:

Required: Only mandatory fields (minimum for a functional listing)
Recommended: Mandatory fields plus recommended attributes (better visibility)
Custom: You select the columns yourself

Recommendation: Start with "Recommended." The additional columns improve listing quality and ranking potential.

Step 3: Download the File

The downloaded Excel file contains multiple tabs:

Template: Where you enter your product data
Data Definitions: Explanation of every column with allowed values
Example: Sample entries for reference
Valid Values: Dropdown values for specific fields (e.g., color codes)

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Key Columns Explained

Available columns vary by category, but these core columns appear in nearly every Flat File:

Column	Description	Example
feed_product_type	Product type within the category	homeaccessory
item_sku	Your internal product number (unique)	MyProduct-001
external_product_id	EAN or UPC	4260123456789
external_product_id_type	Type of external ID	EAN
item_name	Product title (max. 200 characters)	Stainless Steel Travel Mug 500ml
brand_name	Brand name	MyBrand
standard_price	Selling price	29.99
quantity	Inventory count (for FBM)	100
bullet_point1-5	The 5 bullet points	Double-wall insulated...
product_description	Product description	Detailed description...
main_image_url	URL to main image	https://...
other_image_url1-8	URLs to secondary images	https://...
parent_child	Parent or Child (for variants)	parent / child
parent_sku	SKU of the parent product (for children)	MyProduct-Parent
variation_theme	Variation type	Size / Color / SizeColor
update_delete	Action: Update or Delete	Update
fulfillment_channel_code	Shipping method	DEFAULT (FBM) or AMAZON_NA (FBA)

Tip: If you leave a column empty, that attribute remains unchanged during the upload. This is useful for partial updates -- you can change only the "standard_price" column and leave everything else blank.

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The Upload Process

1. Fill Out the Flat File

Open the Excel template and enter your product data in the "Template" tab. Check the "Data Definitions" for the format of each column. Pay special attention to:

Decimal separator: Period, not comma (29.99, not 29,99)
Date format: YYYY-MM-DD
Text fields: No HTML tags, no special characters beyond those permitted

2. Validate Your File

Before uploading, check for obvious errors:

Are all required fields populated?
Are SKUs correct (no duplicates)?
Are EANs valid and properly formatted?
Do variants align (every child has a parent SKU)?

3. Start the Upload

In Seller Central, go to Catalog > Add Products via Upload
Select "Upload your Inventory File"
Choose the file type (Inventory Files for new products, Price & Quantity Files for updates)
Upload the file

4. Review the Processing Report

After the upload, Amazon generates a Processing Report. You can find it under "Monitor Upload Status." The report shows:

Successfully processed rows: These listings were created or updated
Warnings: The listing was created, but an optional field had an issue
Errors: These rows were not processed -- with an error description

Always review the Processing Report completely. An upload with 200 rows and 15 errors means 15 products were not created or updated.

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Common Mistakes and Solutions

Wrong Category

You used a Flat File for Category A, but your product belongs in Category B. Amazon reports: "The SKU does not match any ASIN." Solution: Download the template for the correct category.

Missing Required Fields

Amazon reports: "Missing required attribute." Check the "Data Definitions" -- every field marked as required must be populated. Commonly forgotten: brand_name, external_product_id_type, feed_product_type.

Encoding Issues

Umlauts and special characters display incorrectly. This happens when you open and save the file with a text editor instead of Excel. Solution: Always work with Excel or Google Sheets and save as .xlsx.

EAN Already Assigned to Another ASIN

Amazon reports: "The product data provided conflicts with the Amazon catalog." This means your EAN is already linked to a different product. You will be assigned to the existing ASIN, or you need to correct the EAN.

Variant Errors

Parent-child relationships are the most error-prone part of Flat Files. Ensure:

The parent has "parent" in the parent_child field
Every child has "child" in the parent_child field and the parent SKU in the parent_sku field
All children use the same variation_theme
The parent has NO price and NO quantity

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Flat Files and Repricing

Flat Files are a static tool. You set a price, upload the file, and the price stays until you manually change it. This works for the initial catalog upload but not for ongoing price optimization.

After the Flat File upload, the real work begins: your products are live, competitors react, prices shift. Now you need a tool that responds dynamically to the market.

A repricer like arbytrage.io handles exactly this task. After your listings are created via Flat File, you import your catalog into arbytrage.io, set minimum and maximum prices along with your preferred strategy, and the repricer automatically optimizes your prices in real time from that point forward.

Try arbytrage.io free for 14 days -- the next step after your Flat File upload.

The typical workflow:

Create the Flat File and upload products with static prices
Import your catalog into arbytrage.io
Set minimum and maximum prices per product (minimum price = your break-even plus desired margin)
Choose a repricing strategy (BuyBox Match, Undercut, Step-Jump)
Activate -- from now on, your prices are optimized automatically

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Frequently Asked Questions

Can I use Flat Files to update prices without creating new listings?

Yes. Use the "Price & Quantity" feed instead of the full Inventory File. This feed requires only three columns: SKU, price, and quantity. It is significantly faster and less error-prone than a full upload.

How long does Amazon take to process a Flat File?

Typically 15-30 minutes for smaller files. For very large files (5,000+ rows), processing can take several hours. Avoid uploading large files during peak times.

Can I use the same Flat File for multiple marketplaces?

No. Each Amazon marketplace has its own Flat File templates. The column structure can differ between Amazon.de and Amazon.fr. You need to create a separate file for each marketplace.

What happens if I accidentally upload incorrect data?

You can correct the data by uploading a new Flat File with the correct values. Amazon overwrites the existing data. For serious errors (wrong product assigned to wrong ASIN), you may need to contact Seller Support.

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