External Seller ID [external_seller_id] Field for Product Feed

Required for marketplaces with multi-seller accounts

The external_seller_id attribute is used by marketplaces to identify specific sellers when uploading products to a multi-seller Merchant Center account. It ensures consistent tracking of sellers across countries or languages.

When to use

• Required if you are a marketplace representing multiple sellers in a multi-seller account.
• Not used for single-seller accounts.
• The same seller on the same marketplace must always have the same ID across all feeds and countries.

Format

Follow these formatting rules so Google can correctly process your seller data.

• Type: String (ASCII characters)
• Limits: 1–50 characters, case-sensitive, decimal digits, hyphens, underscores, periods, tildes
• Pattern: [0-9a-zA-Z.~_-]{1,50}
• Repeated field: No

Example formatting:

Minimum requirements

• Only use this attribute if you manage multiple sellers in one account.
• Use UTF-8 encoding to avoid character compatibility issues.
• Ensure the same seller always has the same ID across all countries and languages.
• Do not include whitespace, commas, parentheses, or disallowed characters.

Official Source: https://support.google.com/merchants/answer/11537846