How to sync two Shopify stores
There are three ways to keep two Shopify stores in step, and the right one depends less on your catalogue size than on how often it changes and how much attention you can spare. All three have the same last step, which most guides skip: checking that the stores actually match.
Step 1. Decide which store owns the catalogue
One store has to be the source of truth. Usually it is the store where your team already works: the one connected to your supplier feeds and your product photography. The other store receives products and is edited as little as possible.
Skipping this decision is what makes sync projects painful later, and it is the whole reason one-way sync is simpler than two-way.
Step 2. Choose how the copies are kept
By hand, with CSV exports. Free, and fine for a catalogue that changes a few times a year. Export products from one store, import into the other. Stock goes stale between exports, and every import risks overwriting fields you did not intend to touch.
With a feed or a script. Full control, and someone has to own it. The work is not the first version; it is the year after, when Shopify changes an API version and a variant renaming quietly breaks the matching.
With a sync app. Minutes to set up, a monthly price, and the important differences between apps are what they copy, what they do when unsure, and whether they can prove the result.
Step 3. Map stock locations before the first write
Stock in Shopify lives per location. Decide which locations in the sending store represent the stock you are sharing, and which single location in the receiving store should carry the total. Getting this wrong is the most common cause of numbers that look wrong on day one.
Third-party fulfilment locations are worth checking here too: they often should not be counted, and in StoreTwin they are included only when you leave the selection empty.
Step 4. Verify, do not trust
Whatever method you chose, the copies drift. Before you rely on the setup, decide how you will find out. A green status light in an app is not verification; a list that names the product and the field is.
StoreTwin does this part continuously: hourly for what changed, nightly for the whole catalogue, with a report you can read and a weekly email summarising the week. The free plan runs that audit over a catalogue of any size, including one another app is syncing.
Setting it up with StoreTwin
Install the app on both stores. In the store that owns the catalogue, create a pairing code; in the receiving store, paste it. The first check runs immediately and shows what matched and what needs a decision - nothing is copied yet. Then allow changes in the receiving store and press start syncing.
The full walkthrough · Pricing · What can and cannot be copied