Shopify Back in Stock Notifications: Flow and Apps

Shopify back in stock notifications start with Shopify Flow, which has a Product variant back in stock trigger that fires when a variant goes from zero or less to one or more, and can republish the product, tag it, move it into a collection or email your team. Shopify’s workflow examples also list a Shopify Messaging template, “Email waitlisted customers when a product is back in stock”. The pages cited here do not describe a “notify me” button on the product page, so the part that records a shopper’s request usually comes from a back-in-stock app.

The trigger and settings come from Shopify’s Help Center pages on the back in stock trigger, hiding out-of-stock products and selling when out of stock (read October 23, 2026). The template name comes from Shopify’s workflow examples page, which does not explain how shoppers join the waitlist.

What Shopify gives you natively

The Product variant back in stock trigger starts a workflow when a variant’s inventory rises from 0 or less to 1 or more, whatever caused it: an order, a manual adjustment or an app that changes inventory. The product must have Inventory tracked turned on, and Shopify notes that draft orders do not count as inventory changes for this trigger.

A workflow started by this trigger can use any action that works on products or variants, including:

• Publish product (and Unpublish product for the reverse case);
• Add product to collections or Remove product from collections, for a “Back in stock” collection;
• Add product tags and Remove product tags;
• Update product metafield or Update product variant metafield, for example to switch a “restocked” badge on;
• Create redirect URL and Delete redirect URLs, if you redirected a sold-out product’s page and want it back.

To test a workflow, change a variant’s inventory from 0 to 1 or more and check the workflow ran.

So with the trigger alone you can make a restocked product reappear, flag it on the storefront and tell your staff. To email the shoppers who wanted it, something has to hold their requests: open the Shopify Messaging waitlist template in Flow to see how it does that, or use an app.

Let customers sign up for alerts

To email shoppers when an item returns, you need somewhere to record their request. The usual route is a back-in-stock app from the App Store, which adds a “notify me” button to sold-out variants, stores each request with the variant, and emails or texts the shopper when stock comes back; some also connect to Flow, which their listings state. Compare apps on three points: whether alerts work per variant, whether they send by email and SMS, and whether a restock alert also asks for marketing consent separately, because a request for one product is not permission to send newsletters.

Check how an app, or the Shopify Messaging template, records each request before you rely on it: the alert needs the variant the shopper asked about as well as an email address.

Sold-out products on the store

Before alerts, decide what a sold-out product does on your store. Shopify gives three options:

1. Keep it visible, not buyable. The default: once tracked inventory hits zero, customers cannot buy it. This is where a “notify me” button belongs.
2. Keep selling when out of stock. Check Continue selling when out of stock in the product’s Inventory section for preorders or stock that is on its way. It needs Inventory tracked on, and it does not apply to Shopify POS, which warns staff instead.
3. Hide it. Add the condition Inventory stock is greater than 0 to automated collections (with Match all conditions), override the default /collections/all catalog with your own collection, or use Flow’s Publish and unpublish products based on inventory level template.

With several locations, a product shows as out of stock online if the locations that fulfill online orders have none, even when a retail-only location has stock. Add stock where online orders are fulfilled. And if you use a dropshipping app and products show as sold out despite stock, Shopify’s Help Center points to missing shipping rates for the app’s location.

Build a restock workflow

A practical first workflow:

1. In Shopify Flow, start a new workflow with the Product variant back in stock trigger.
2. Optionally add a condition, for example only products with a tag such as restock-alert, so the workflow ignores routine top-ups.
3. Add Publish product, if you unpublish sold-out items.
4. Add Add product to collections with a “Back in stock” collection featured on your homepage.
5. Add the Flow action Send internal email so someone on your team updates social posts or the newsletter.
6. Turn it on and test by moving one variant from 0 to 1.

Pair it with the reverse: when inventory drops to zero, unpublish or move the product to an “Out of stock” collection. Our guide on how to automate orders with Shopify Flow covers Flow’s basics, and accurate stock counts start with consistent SKUs; see Shopify SKU and barcode. More inventory topics are in the inventory and catalog hub.

FAQ

Does Shopify have back in stock notifications? Shopify Flow has a Product variant back in stock trigger for automating store actions when stock returns, and Shopify lists a Messaging template for waitlisted customers. Recording who asked to be notified usually needs a back-in-stock app.

When does the Flow back in stock trigger fire? It fires when a variant’s inventory goes from 0 or less to 1 or more, from any source such as an order, a manual change or an app. The product must have inventory tracking on.

Should I hide sold-out products? Hide them if they will not return soon. Keep them visible with a “notify me” option if they will, so shoppers can still find the page and ask to be told.

Can customers still buy when a product is out of stock? Customers can buy out-of-stock items when you check Continue selling when out of stock on the product, which suits preorders and stock already on its way.