Overview

Amazon sellers encounter Error 97778 when the Harmonized System Nomenclature (HSN) code entered on a product listing does not meet Amazon’s strict four‑digit numeric format. The validation blocks the listing from going live, causing delays that can affect launch schedules and inventory availability. Fixing the issue quickly restores listing flow and keeps sales pipelines intact.

Key Points

• Exact four‑digit requirement — Amazon accepts only HSN codes that consist of four numeric characters; any entry with three, five, or six digits is rejected.
• Leading zeros are mandatory — A code such as “85” must be entered as “0085” to satisfy the four‑digit rule; omitting the zeros triggers the error instantly.
• Numeric characters only — Letters, hyphens, spaces, or any special symbols in the HSN field cause validation to fail.
• Hidden characters from copy‑paste — Transferring codes from spreadsheets, PDFs, or web pages can embed invisible spaces or formatting marks that Amazon reads as invalid characters.
• Spreadsheet auto‑formatting — Programs like Excel often strip leading zeros automatically, converting “0012” to “12” and unintentionally creating the error.
• Impact on GST compliance (India) — In markets where HSN codes are tied to tax reporting, an incorrect entry not only blocks the listing but also jeopardizes accurate GST filings.

How HSN Code Validation Works

1. Entry Capture — When a seller types or pastes an HSN code into the listing form, Amazon’s front‑end script records the raw string. Example: a seller pastes “85 ” (note the trailing space) from a spreadsheet.
2. Pattern Check — The system runs a regex test that allows only four consecutive digits (0‑9). If the string deviates—by length, by containing non‑numeric symbols, or by having hidden whitespace—the validation fails. Example: “0085” passes; “85” or “0085‑A” fails.
3. Error Flagging — Upon a failed check, Amazon returns Error 97778, highlights the HSN field, and prevents the listing from being saved or uploaded.