Guides

Shopify Plus expansion stores, and the inventory they don't share

An expansion store is an extra store on your Shopify Plus contract: ten stores in total at no extra cost, sharing staff and billing with the main store and nothing else — not products, not orders, not inventory. Who qualifies, how to create one, when Markets is the better answer, and how to keep the stock in sync.

A Shopify expansion store is an additional store on your Shopify Plus contract — a separate .myshopify.com store in the same organization, with its own settings, products, orders and inventory. A Plus organization can hold ten stores at no extra cost, one main and nine expansion, and manages their staff and billing in one place. That is everything they share.

So no — expansion stores do not share inventory with your main store. Shopify’s own documentation is unambiguous about it: “Store settings, products, collections, and inventory aren’t synced between stores.” If two stores sell from the same physical shelf, keeping the counts in sync is something you add.

The longer answer starts a step earlier — with whether you need the second store at all — because every second store you avoid is an inventory sync you never have to run, maintain or debug.

This is the Shopify Plus version of a question with four guides. Expansion stores are the subject here. The general versions are which architecture, which method and which routine — all of which apply unchanged, because an expansion store is an ordinary store with a Plus contract around it.

What does an expansion store share with the main store?

Two things, and it is worth being exact, because several guides to expansion stores imply more. Everything below comes from Shopify’s expansion stores documentation, read on 15 November 2026.

How you create one, and how many you get

Shopify puts the allowance plainly: a Plus organization can hold a maximum of ten stores on its contract at no additional cost — one main store and nine expansion stores. Staging stores don’t count towards the ten. Past ten, you talk to Shopify Support; a store created beyond your contract’s limit starts as a trial store and asks you to approve an extra fee.

Creating one is a few clicks rather than a project: Settings → Organization → Create store, choose Production or Staging, give it a name and URL, and optionally import data from an existing store on the way in. The main store needs a payment method and a complete billing address first.

The import is the moment worth slowing down for. It is offered only while you create the store, and it copies three things: themes; products, variants and collections with their metafields (except reference-type and category metafields); and files. Stock levels, customers and orders are not on Shopify’s list, and nothing is kept in sync afterwards. A theme that hard-codes file links will still point at the original store. And a catalogue copied once and then edited in two places is how two stores stop lining up — the SKU mismatches discussed below start here.

Who qualifies: same brand, same goods

Shopify sets three eligibility conditions for expansion stores on a standard Plus contract. The store must be “identical to the main brand” in store name and branding, carry the same types of goods and services, and be billed in USD or INR.

That rules out a use some guides list first. A second brand, or an acquired brand you are keeping separate, does not qualify as an expansion store on a standard contract — it needs its own store on its own plan, unless your contract with Shopify says otherwise. Its inventory is exactly as separate either way, so everything below still applies.

Do you actually need a second store?

This is not a rhetorical question. A large share of expansion stores exist to solve problems that Shopify solved inside a single store some time ago.

Selling internationally

Shopify Markets handles multiple currencies, country-specific domains, market-level pricing, duties and translations — all from one store, one catalogue, one set of inventory. If your reason for an expansion store is “we need a .de domain in euros”, Markets very likely covers it, and covers it with zero sync problem because there is only ever one quantity. The guide to stores for different countries walks through where Markets stops.

Selling wholesale

Shopify B2B runs inside the same store using company profiles, buyer-specific catalogues and price lists. Retail and wholesale draw down the same inventory automatically. A separate B2B store is worth it when wholesale is a different legal entity or ships from a different warehouse — not merely because the pricing differs. More in wholesale and retail stores.

The general rule: one store with many locations beats many stores whenever it is possible at all. Locations inside a store are consistent with each other by construction. Stores are consistent with each other only because something keeps making them so.

When is a separate store the right call?

Plenty of cases genuinely need one:

• A separate legal entity — different company, tax registration, or payment processing that has to be cleanly split.
• A different fulfilment operation — a regional warehouse or 3PL with its own processes, where blending the operations would be worse than syncing them.
• A different range of the same goods — where the overlap is a subset of SKUs rather than the whole range.
• Partner- or franchise-operated storefronts — someone else runs the store day to day and should not have access to yours.
• Genuinely divergent theme or checkout requirements that cannot coexist in one store.
• A different brand — a real reason for a separate store, but not for an expansion store on a standard contract, as above.

In all of these, the shared-inventory problem is real and unavoidable — because the stores are separate on purpose, but the shelf is not.

Why doesn’t the stock follow between stores?

An expansion store is a full Shopify store. Same architecture as any other: its own products with their own IDs, its own orders, its own inventory records per location. Belonging to the same Plus organization gives you one contract and one place to manage staff — not shared stock.

So if your Berlin expansion store and your main store both sell an item that lives on one shelf in one warehouse, both stores are independently advertising and decrementing their own private count of it. They will diverge, and the divergence always sells you into trouble in the same direction.

How do you keep two stores in sync?

Decide which store owns the number

Before any tooling: pick the source of truth. Usually the store closest to the physical stock — the one your warehouse or 3PL already updates. Every other store follows it, and nobody edits stock anywhere else. One-way, one owner.

Two-way sync that copies whole quantities between expansion stores sounds appealing and is usually a mistake. The moment both sides can overwrite each other, you need a rule for what happens when both change at once, and every such rule oversells in some scenario. The two-way that holds up is one shared count that each store’s sales are applied to as changes, so simultaneous sales both land.

Get the SKUs identical first

Nothing can match products across stores by internal ID, because the IDs are per-store. Matching happens on SKU. Expansion stores are especially prone to SKU drift because they are usually created by importing a catalogue and then editing it — regional suffixes get appended, variants get renamed, and a year later the two catalogues no longer line up.

Export products from both stores and check for three things: SKUs present in one store only, blank SKUs, and the same SKU on two different variants inside one store. That last one decides what you can run. A one-way mirror has no correct target for it — copy the count to which variant? — and a tool that picks one will be silently wrong. Shared stock can give those variants one count, but only if they really are one item, like the same shirt listed twice; that is a decision for you to make, not for a tool to guess. The free duplicate SKU checker runs all three checks on two product exports, in the browser.

Choose the mechanism

A few apps are sold specifically for expansion stores, and they copy more than stock. Edition ‑ Expansion Store Sync pushes products, collections, pages and blogs from one master store and syncs inventory both ways, from $25 a month for 1,000 products. Syntonic Multi Sync syncs products one way and inventory both ways, free to 250 variants. Gro Multi Store Sync charges per connected store. All three were new in 2025 or 2026 and had five reviews or fewer when we read them on 15 November 2026. What every sync app costs puts them beside the rest.

Allocate rather than mirror, if the stock is not really shared

Worth naming because it is common in expansion-store setups: sometimes the regional store should not see the full global quantity. If 300 units sit in the EU warehouse and 700 in the US, mirroring one number into both stores advertises stock that cannot ship to that customer in any reasonable time.

When that is your situation, the right model is Shopify locations plus per-market fulfilment rules inside one store — not two stores mirroring each other. Mirroring is correct when both stores draw from the same physical stock; it is wrong when they draw from different ones.

What should you check once it is running?

• Change a quantity in the main store and confirm it lands in each expansion store.
• Change one in an expansion store and confirm it is not pushed back — and that everyone on the team knows that edit will be overwritten.
• Run a comparison across all stores on a schedule, not once at setup. Drift is a slow leak, and finding it needs an explicit check rather than a glance.
• Confirm you get told when a write fails. Silent failure is the default state of every integration nobody is watching.
• Re-check which SKUs matched after any catalogue change in either store — that is when matching quietly breaks.

Where does StockUnison fit?

StockUnison is built for exactly the mirroring case: one main store’s quantities, one way, into as many other stores as you connect — or, when every expansion store sells from the same shelf, one shared count per SKU that a sale in any of them lowers. Products are matched by SKU, SKUs it cannot match are reported rather than guessed, preview mode shows every change before anything is written, and a difference check compares every matched SKU across every connected store. One store carries the subscription — the main store, or the store that started sharing — and every other store installs free. Every connected store is included on every plan, so the price follows the catalogue, not the number of expansion stores: $19/month up to 2,500 SKUs, $29 to 10,000, $59 to 100,000 and $99 to 250,000.

It is the wrong tool if you need per-region allocation rather than mirroring, or if you need products and prices copied as well as quantities.