Overview

Error 90148 is a product listing validation error that Amazon returns when a seller submits a feed or listing update containing an attribute name that the system does not recognize. This error typically surfaces during flat file uploads, inventory feed submissions, or API-based listing creation, and it prevents the affected listing data from being processed until the invalid attribute is corrected.

Key Points / What Sellers Need to Know

• Unrecognized attribute names trigger this error — Amazon's catalog system validates every field name in your submission against the allowed attributes for the product category you're listing in. If a field name doesn't match, Error 90148 is returned.
• The error message identifies the problem field — The error response includes the specific attribute name that was not recognized, displayed as "Unknown attribute '{attribute_name}'," making it straightforward to locate the issue.
• Category-specific templates matter — Each Amazon product category has its own set of valid attributes. An attribute that works in one category may not exist in another.
• Flat file formatting is a common cause — Misspelled column headers, outdated template versions, or extra columns in flat file uploads are frequent sources of this error.
• API and feed submissions are also affected — Sellers using SP-API, third-party listing tools, or bulk upload feeds can encounter this error if their data schema doesn't align with Amazon's current attribute definitions.

Common Causes

The most frequent reason sellers encounter Error 90148 is using an outdated or incorrect listing template. Amazon periodically updates the attributes available for each product category, and templates downloaded months ago may contain field names that have since been renamed, deprecated, or reorganized. Similarly, manually editing flat files can introduce typos in column headers — even a single misplaced character in an attribute name will cause the system to reject it as unknown. Sellers who copy templates between categories or reuse old spreadsheets are especially prone to this issue.

Another common scenario involves third-party listing software or custom integrations that pass attribute names Amazon no longer supports. When Amazon updates its product type definitions or migrates categories, previously valid attribute names can become obsolete without advance notice to sellers relying on those field names in their automated workflows.