Link Existing Shopify Products to Supplier Inventory

You already built the storefront. Custom photos. Brand voice in the titles. SEO descriptions you spent a weekend on. Then you connected a wholesale supplier and realized the sync engine is built for importing new products — not for the listings you already polished.

Product Mappings closes that gap. You manually link each existing Shopify product (or variant) to the matching supplier SKU, set Update Settings so sync preserves your custom fields, and Supply Master keeps inventory and pricing current without overwriting the work you already did.

This article walks through when to use Product Mappings, the Import Preserves banner you should confirm on camera, and the step-by-step flow in the app.

Running example: Lakeview Decor Co. imported 200 Bella+Canvas blanks through Supply Master, then spent three weeks shooting lifestyle photos and rewriting titles for their top 40 SKUs. They need S&S inventory on those 40 without a sync wiping the new images.

Key Takeaways

• What this article shows — how Product Mappings link hand-built Shopify listings to supplier SKUs while preserving custom product fields and images.
• Who it's for — merchants with an existing catalog (custom photos, titles, or descriptions) who want supplier inventory and pricing without a full re-import.
• The fast answer — enable the Product Mappings editor under Advanced Settings, set Update Settings to Only Variant Fields (or Only Inventory), add mappings row-by-row, confirm the Import Preserves banner, then run sync.
• What it doesn't do — mappings don't replace a full import for net-new SKUs; products Supply Master imported automatically are already linked and don't need manual mapping.
• Try it now — Install Supply Master free on the Shopify App Store (5.0★, top-rated for apparel-supplier integration in the U.S. and Canada).
• Want help? — Email support@comstack.com and a Comstack engineer will configure mappings with you.

See It in Action

Enable Product Mappings, set Import Preserves, link existing Shopify products to supplier variants, and confirm inventory sync without overwriting custom fields.

Table of contents

• When Product Mappings beat a fresh import
• Set Update Settings before you map
• Enable the Product Mappings editor
• Add mappings row by row
• Confirm Import Preserves
• FAQ
• Try it on your store

When Product Mappings beat a fresh import

Use Product Mappings when:

• You already have branded or custom-designed products in Shopify.
• You've customized images, names, or descriptions and want to preserve them.
• You want Supply Master to update only inventory, pricing, or variant-level fields on those products.

Products Supply Master imported directly are already linked to the supplier — they do not need manual mapping.

For the Help Center walk-through with screenshots, see linking existing products to supplier inventory.

Set Update Settings before you map

Before you add any mappings, open Edit Supplier > Automatic Sync and set Update Settings to Only Variant Fields (or Only Inventory if you only need stock updates).

If you leave All Fields with Images enabled, every sync can overwrite your custom titles, descriptions, and images on mapped products — the opposite of what Product Mappings are for.

Enable the Product Mappings editor

1. Navigate to Edit Supplier > Advanced Settings.
2. Set Product Mappings Editor to Enable Product Mapping Editor.
3. Save — the Product Mappings tab appears on the supplier screen.

Add mappings row by row

On the Product Mappings tab:

1. Click Add Mapping.
2. Select the Shopify product (or variant) you want to link.
3. Match it to the supplier product and variant.
4. Save the row.

Repeat for each existing listing that should receive supplier inventory and pricing updates.

Confirm Import Preserves

After you save mappings, the Product Mappings tab shows an Import Preserves banner listing which fields stay untouched versus which fields sync from the supplier.

Before you rely on automatic sync, confirm Product fields and Images appear under Import Preserves — not under Import Overwrites. If product fields or images show under overwrites after you set Update Settings, fix the settings and re-save before the next sync.

FAQ

Will mappings overwrite my custom photos?

Not when Update Settings is Only Variant Fields or Only Inventory and the Import Preserves banner lists images under preserves.

Do I need mappings for products Supply Master imported?

No — those products are already linked automatically.

Can I map one Shopify product to multiple suppliers?

Each mapping row links one Shopify product to one supplier variant for that supplier connection. Multi-supplier setups use separate supplier connections with their own mapping tables.

Related reading

• Make Your Supplier's Catalog Look Like Your Own Storefront — learn how to map supplier fields directly to Shopify product attributes.
• Smart Merchandising: Fine-Tune Which Supplier Products Land in Your Store — understand how Auto-Create modes control what sync adds.
• Control How Orders Get Sent to Your Supplier — once mapped, configure how your Shopify orders get handed off to your supplier.

Try it on your store

1. Install Supply Master and open the supplier you want to map.
2. Set Update Settings, enable the editor, add your first mapping, and confirm Import Preserves before running sync.
3. Email support@comstack.com if you want a Comstack engineer to walk through mappings on a live store.