1. Purpose
Read a catalogue where several listings share a SKU, find the one variant that actually holds the stock and the settings, and make your changes in the one place they will take effect.
2. Scope
Understanding how variants link to a primary, reading the Primary and Linked badges, and knowing which record to configure. Building a bundle's component list from a CSV is SWI-013. Setting up Shopify inventory after connecting a store is SWI-018.
3. Roles & Responsibilities
Role | Responsibility |
|---|---|
Brand owner | Owns the SKU scheme on the store side, and decides when two listings are genuinely the same item. |
Account manager or 3PL admin | Identifies the primary for each SKU, and makes bundle, weight and packaging changes on it rather than on a copy. |
Support | Confirms which variant is primary before advising on stock or allocation, since a linked variant reads as empty by design. |
4. When you need this
The same product appears several times in Products, usually after a store listing was recreated or duplicated.
A variant shows zero available while you know the stock is there.
A multi pack looks like it has no bill of materials attached, so it appears to be an independent SKU rather than a bundle.
You changed a weight, a bundle or a packaging setting and it did not take effect.
You are about to tidy the catalogue and want to know which records are safe to leave alone.
5. Key concept: a linked variant is a pointer, not a copy
What people assume | What actually happens |
|---|---|
Two listings with the same SKU are two separate items, so Ship Side Kick has to choose between them. | They are one item. One variant is the primary, and every other variant carrying that SKU points at it. There is nothing to choose. |
A variant showing zero available is out of stock. | Linked variants always show zero. The stock sits on the primary, and an order against any linked variant draws from it. |
No BOM tag means no bundle is configured. | Only the primary carries the BOM tag. A linked multi pack shows a blank BOM column even when the bundle is configured and working. |
Each listing needs configuring separately. | Configure the primary only. Weights, bundles and packaging set on a linked variant do not drive fulfilment. |
Linking is something you switch on. | Duplicate SKUs link automatically. Aliases are the manual part, and only for SKUs that are not identical. |
A multi pack holds its own stock. | A pack SKU with a bundle derives its availability from its components. A base SKU with 900 units shows 450 on the two pack and 300 on the three pack. Those numbers move together because they are the same stock. |
6. Procedure
6A. Switch to the Variants view
The default Products view mirrors how the store groups things, which is the view that makes duplicate SKUs hard to read. The Variants view lists one row per variant and is the better place to start.
Go to Products in the left navigation.
Click Variants at the top of the table.
Search for the SKU you are interested in. Every listing carrying it appears together.
6B. Identify the primary
Each row carries a badge showing its role.
Primary is the record that holds the stock and the settings. There is exactly one per SKU.
Linked points at a primary. It is a live sales listing, but it is not where anything is configured.
Linkable shares a SKU with something else but has not been linked yet, and is worth a look.
Use the Primary and Linked filters above the table to narrow the list. Filtering to Primary is the fastest way to see the catalogue as the warehouse sees it, with one row per real item.
6C. Make your changes on the primary
Open the primary variant.
Make the change there, whether that is the weight, the packaging, the bundle or the supplier.
Check the linked variants listed on that record. That list is every store listing the change now covers.
Nothing needs repeating on the linked records, and a change made on one of them will not reach fulfilment.
6D. Link a SKU that is not an exact match
Duplicate SKUs link on their own. When two listings mean the same item but spell the SKU differently, the other spelling goes on the primary as a SKU alias.
SWI-036 covers that job in full, including where an alias is honoured and where it is silently ignored. Use it rather than this section.
7. Verification
Filtering to Primary shows one row per real item, with the stock on it.
Opening a primary lists the linked variants beneath it, and the count matches the number of duplicate listings you expected.
A pack SKU with a bundle shows an availability that is its component stock divided by the pack size, and it moves when the base SKU moves.
An order against a linked listing produces picks for the primary's components, not for the linked record.
After adding an alias, the other listing reports as linked rather than linkable.
8. Constraints and caveats
There is exactly one primary per SKU. If a SKU somehow has none, nothing can resolve to it, and it needs fixing before that SKU will behave.
Linked variants showing zero stock and a blank BOM column are correct and expected. Do not read either as a fault.
Duplicate listings accumulate quietly. Every time a listing is recreated on the store side, another linked variant appears, and the catalogue gets longer without anything breaking.
Matching is on the SKU itself, not on the store's product identifier, so renaming a listing changes nothing about linking.
An alias whose value is shared across different products will link unrelated items. Keep aliases specific.
Archiving a primary does not move its role to another variant. Sort the primary out before archiving anything.
Very long product names from marketplace listings can push the table layout wide and make these views harder to read.
9. Worked example
A multi pack catalogue reads as broken to anyone expecting each pack to explode into units of a single base SKU, which is how an ERP usually presents it. The list views show blank bill of materials columns and variants sitting at zero, and the configuration underneath is correct.
Observation | Reading |
|---|---|
The same product appears as two listings, with overlapping SKUs across their variants. | Both listings are live on the store and both have been imported. Normal, and not itself a problem. |
Several variants carry the base SKU, all but one showing zero available. | Those are the linked ones. The remaining variant is the primary and holds the entire balance. |
The multi pack rows show a blank BOM column. | Only the primary for each pack SKU carries the tag. The bundles are configured and correct. |
The two pack, three pack and five pack show availability that is neatly half, a third and a fifth of the base stock. | Confirmation the bundles are live. Pack availability is derived from component stock, so those ratios are the bundle working. |
A live order for one five pack generates a pick for five units of the base SKU. | The explosion is already happening, on every order. |
No configuration change is needed in this pattern, because the catalogue is already structured the way it is expected to be. What is missing is any indication in the list views that a linked row points somewhere, which is what makes a correct setup read as a broken one.
10. Related documents
SWI-036 — Add a SKU Alias So a Second SKU Finds the Same Product
SWI-013 — Upload Product Bundles from a CSV
SWI-004 — Read the Inventory Screen
SWI-018 — Set Up Shopify Inventory After Connecting