Back in stock notifications: the complete Shopify guide
Why back-in-stock alerts convert so well, and how to set them up without slowing your store.
A sold-out product page is one of the few places in your store where a shopper has already decided what they want. They found the product, picked a size, maybe read the reviews. The only thing missing is stock. A back-in-stock notification turns that moment into a promise: we will tell you the second it is back.
What is a back-in-stock notification?
It is a message (usually an email, sometimes SMS, WhatsApp or web push) sent automatically to shoppers who asked to be told when a sold-out product or variant becomes available again. The shopper signs up with a short form on the product page, and your app watches inventory and sends the alert when stock returns.
Why these alerts convert so well
- Intent is already there. The shopper chose the product and the variant before they signed up.
- Timing is perfect. The message arrives at the exact moment the product can be bought.
- It is expected. People asked for this message, so it is opened and clicked far more than a regular campaign.
What a good setup looks like
- Variant-level signups. Size M sold out is not the same as the product sold out. Let shoppers pick the exact variant.
- A form that looks like your store. A generic pop-up that clashes with your theme lowers trust. Match your fonts, colours and buttons.
- Fast alerts. Aim for under a minute from restock to first message. Hot items can sell out again in an hour.
- Staggered sends when stock is low. If 10 units come back and 300 people are waiting, send in waves so you do not disappoint 290 people at once.
- A reminder. One follow-up to people who did not buy the first time, while stock lasts.
- Consent you can prove. Store what the shopper agreed to, and use double opt-in where the law asks for it.
Do not forget performance
Every app script on your product page costs load time. Look for apps that load asynchronously, avoid API calls on page load and only load the form on sold-out variants. With WaitCherry, the storefront script stays under 15 KB gzipped.
Measure what it earns
The number that matters is revenue from orders placed after an alert. Count the line item that was restocked, not the whole cart, so your report stays honest.
Try it: WaitCherry builds a theme-matched notify-me form for you in minutes, with alerts by email, SMS, WhatsApp and web push. See back in stock alerts.