If you keep stock in more than one place in Shopify, Shuttle needs to know which location's stock to send to Etsy. It also needs to know where to change stock when an Etsy sale or update comes in. The Shopify inventory location settings decide both, so your Etsy quantities match the stock you actually sell from.
Where to find the Shopify inventory location settings
The Shopify inventory location settings are in Settings > Products > General. What you see there depends on how many locations Shuttle finds in your Shopify store:
One location: Shuttle shows Only one location and uses that location for everything, so there is nothing to choose.
Several locations: you choose a Default Shopify location and tell Shuttle how your stock is spread across locations.
No locations: Shuttle shows No locations found until a location is available in Shopify.
Shuttle keeps its own copy of your Shopify location list. After you add, remove or deactivate a location in Shopify, click Refresh locations so Shuttle loads the current list.
Choose your Default Shopify location
The Default Shopify location is the Shopify location Shuttle reads stock from and writes stock to when it syncs with Etsy. You first choose it when you set up Shuttle, and you can change it at any time.
Go to Settings > Products > General and find Shopify inventory location.
If a location is missing from the list, click Refresh locations.
Choose a location under Default Shopify location.
Click Save.
You cannot select a location that is deactivated in Shopify. Shuttle shows it with (Inactive) after its name.
The Default Shopify location applies to every Etsy shop you have connected. When you save it for one Etsy shop, Shuttle uses it for all of them.
Shuttle can sometimes change the Default Shopify location for you. If your default is deactivated in Shopify and you have only one active location left, Shuttle switches to that location.
Tell Shuttle whether each variation is stocked in one location
The My Shopify variations are stocked in a single location checkbox tells Shuttle whether each variation is stocked in just one place. It is under Single-location stock in Settings > Products > General, and it is checked by default.
Keep the checkbox checked when every variation is stocked at one location only. Shuttle then always uses the stock at one location for each variation and never adds up stock across locations.
Uncheck the checkbox when variations are stocked across several locations. The Quantity source for Etsy updates setting then appears, so you can choose how Shuttle counts that stock.
The checkbox only shows when Shuttle finds more than one location. If you refresh locations and only one is active, Shuttle checks the box for you.
Choose the Quantity source for Etsy updates
The Quantity source for Etsy updates setting decides which Shopify stock figure Shuttle sends to Etsy. It only shows when My Shopify variations are stocked in a single location is unchecked. It has two options:
Use the selected location only (recommended): Etsy gets the stock at your Default Shopify location. Stock at your other locations is not added in.
Use combined quantity across all locations (use with caution): Etsy gets the total stock across all your locations.
With the combined option, Shuttle still changes stock only at your Default Shopify location. When an Etsy sale comes in, Shuttle lowers the stock at that location so your total across all locations matches Etsy.
The combined option can push your Default Shopify location below zero. This happens when an Etsy sale is bigger than the stock held at that location. Your total stays correct, so Etsy shows the right number. To clear the negative stock, move stock to that location in Shopify.
How Shuttle picks a location for each variation
Shuttle does not always use your Default Shopify location. It first checks where each product or variation is actually stocked. These rules apply when Quantity source for Etsy updates is set to Use the selected location only (recommended), or when My Shopify variations are stocked in a single location is checked.
When Shuttle reads a variation's Shopify stock to compare with Etsy or send to Etsy, it works in this order:
If the variation is stocked at your Default Shopify location, Shuttle uses the stock there.
If the variation is stocked at exactly one location that is not your default, Shuttle uses the stock at that location.
If the variation is stocked at several locations and none of them is your default, Shuttle does not pick one. It has no stock figure for that variation until you stock it at your Default Shopify location.
When Shuttle changes stock in Shopify, for example after an Etsy sale or when it copies an Etsy quantity, it works in this order:
If the product is stocked at exactly one location, Shuttle changes the stock there, even when that location is not your default.
In every other case, Shuttle uses your Default Shopify location. That includes products Shuttle creates in Shopify and products stocked at several locations.
If Shopify refuses because the variation is not stocked at that location, Shuttle tries once more. This time it uses the one location where the variation is stocked, if there is only one.
With Use combined quantity across all locations (use with caution), Shuttle sends Etsy your total across locations. It changes stock at your Default Shopify location, and only uses another location when the variation is not stocked at your default.
Errors caused by your Shopify inventory location
Some errors happen because of your Shopify inventory location. Each of these articles explains how to fix one:
Variants could not be created due to invalid location: your Default Shopify location was deleted in Shopify.
Cannot set stock levels. The currently selected Shopify inventory location is deactivated.: your Default Shopify location was deactivated in Shopify.
Cannot update stock levels due to multiple locations conflict: a fulfillment app or service runs one of the locations involved.
Shopify variation is not stocked in the selected inventory location: Shuttle could not read a variation's stock at the location it uses.