Confirming and Mapping Your Master SKU

July 20, 2026

Summary

Step 2 of onboarding: confirm each imported listing is linked to a Master SKU, or map any that are missing, using bulk CSV import or manual per-listing linking.

OVERVIEW

In step 2 of onboarding you confirm that each imported listing is linked to a Master SKU, or map any that are missing. A Master SKU is the product identifier that ties a channel listing to a product in your catalog.

Check Listings — a green circle marks a mapped Master SKU; a red circle marks a listing still missing one.
Import Master SKUs — export the unmapped listings, fill in Master SKU values in the CSV, and upload to map in bulk.
Manual linking — link or create a product per listing from the Product Link section.
Onboarding step 2 — clearing all Master SKUs lets you advance to step 3 in the onboarding flow.

TWO WAYS TO SET A MASTER SKU

Import Master SKUs (bulk)

Channel Listings → Actions → Import → Master SKUs. Select the channel, Export Listings (it auto-selects listings missing a Master SKU), fill the Master SKU column in the CSV, then Upload and Import.

Manually set (per listing)

Channel Listings → filter “Missing Master SKU” → open the listing. In the Product Link section click Select/Create Product, link an existing product or click New Product, then Save Variant.

CSV REQUIREMENTS

Header	Role
SKU	Required. The listing SKU being mapped.
Master SKU	Required. The Master SKU value to assign.
UPC, MPN, ASIN, Title	Populated for identification only. These do not update through the Import Master SKUs tool.

IMPORTANT NOTES

Note: If you upload your own file, the SKU and Master SKU headers must be entered exactly as shown, case-sensitive. Only those two are required to run the import.

Note: UPC, MPN, ASIN, and Title are included in the export to help you recognize each item, but the Import Master SKUs tool does not update them. Use Customizations for those fields.

Note: Rebuilding a listing preserves its current product link, so it will not re-point a listing variant to a different product variant. To change an existing link, use the Product Link picker rather than Re-Build.

COMMON ISSUES

Import Master SKUs completed without errors but the links did not update

Confirm the file used the exact case-sensitive headers SKU and Master SKU and that you selected the correct channel. The Master SKU import resolves to parent Master SKUs, so it cannot re-point a listing variant to a specific sibling variant under the same parent — that scenario needs the Product Link picker or support help.

A listing variant is linked to the wrong product variant and Re-Build will not fix it

Re-Build keeps existing link connections, so it cannot change the linked product variant. Use Select/Create Product in the Product Link section to relink. For multi-variant or bundle listings where the picker only resolves to the parent, contact support to correct the variant-level link.

FAQS

How do I tell if a listing is mapped?

Look for the circle icon next to the product: green means the Master SKU is mapped, red means it is missing.

What columns does Import Master SKUs need?

Only SKU and Master SKU, and the header names are case-sensitive.

Will UPC, MPN, ASIN, or Title update through this tool?

No. They are shown for identification only and are not changed by the Import Master SKUs tool.

How do I set a Master SKU manually?

Open the listing, go to the Product Link section, click Select/Create Product, link or create the product, and Save Variant.

Why did Re-Build not fix my link?

Re-Build maintains existing link connections by design. Use the Product Link picker to change which product a listing is linked to.

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