What Do I Tell Customers Who Want a Sold-Out Product?
Tell them honestly that it’s sold out, offer what you have in stock, and take their name for a back-in-stock message. AeroChat checks live stock in Shopify, suggests in-stock alternatives, and records which item and variant the customer wants. When Shopify shows that variant back in stock, AeroChat messages everyone who asked, on the channel they used. A customer who asked once doesn’t have to keep checking the page.
Shopify behavior from Shopify’s help center: Product variant back in stock trigger in Shopify Flow, checked 11 November 2026.
Why it happens
A product sells out fast, and customers keep asking when it will be back. Merchants on the Shopify Community describe the gaps. One couldn’t find a “notify me” button that works on a featured product on the homepage. Others want it on collection pages with quick add, not just product pages. Some back-in-stock forms stopped working after a theme change or on a store in two languages, and one showed empty labels on products that were in stock. Every broken form is demand you never hear about.
The customers who message you are the ones who want it most. If the reply is a flat “sold out, sorry”, that interest is lost.
What Shopify’s help center says
Per Shopify’s help center, checked 11 November 2026, Shopify Flow has a Product variant back in stock trigger. It starts a workflow when a variant’s inventory goes from zero or less to one or more. The product must have inventory tracking turned on for the trigger to fire.
The usual fixes and their limits
- A back-in-stock app or form, such as Notify Me or an email platform’s form. Works for shoppers who see the button. Theme changes and quick-add collection pages can break it.
- A Shopify Flow workflow. The trigger tells you when stock is back. You still need a list of who to tell and a way to message them.
- A list in a spreadsheet. Someone writes down every request and messages each person later. Easy to start, hard to keep up during a busy launch.
- Taking pre-orders instead. Good when you know the restock date. See keeping pre-order customers updated.
How to handle it in chat with AeroChat
The customer asks about the item in the chat. AeroChat checks stock for the exact variant in Shopify. If it’s sold out, it says so, offers up to two in-stock alternatives, and asks if they’d like a message when it returns. If they say yes, it records the variant against their contact, with their consent. When Shopify reports the variant back in stock, AeroChat sends each of them a message with a direct link. On WhatsApp, that message goes out with an approved template, because it’s sent outside the 24-hour customer service window.
Customer: Will the Willow dress in size 8 come back? (example)
AeroChat: The Willow dress in size 8 is sold out right now. The Hazel dress has a similar cut and is in stock in size 8 (example). Would you like a message here when the Willow is back?
Customer: Yes please.
AeroChat: Done. I’ll message you on WhatsApp as soon as size 8 is back in stock.
Nine days later, on WhatsApp: “Hi Ana, the Willow dress in size 8 is back in stock. Here is the link: [link]”
Copy this into AeroChat
When a customer asks for a product, check stock for the exact size and color in Shopify.
- If it is sold out, say so clearly. Never give a restock date unless it is in our knowledge base.
- Suggest up to two similar products that are in stock in their size.
- Ask if they want a message when it is back. If they say yes, tag their contact with the product and variant, for example “waitlist: willow-dress-8” (example).
- When Shopify shows that variant back in stock, message every contact with that tag, using our approved back-in-stock template on WhatsApp. Include the product link.
- Remove the tag once the message is sent.
Reply in the customer’s language.
Get your WhatsApp back-in-stock template approved before you turn this on. A starting point is in our back-in-stock templates.
What to connect
- Your Shopify store. Built in. Install AeroChat from the Shopify App Store and connect your store. AeroChat reads live stock and learns when a variant is back. Inventory tracking must be on for those products.
- WhatsApp, Instagram or Messenger. The channels where customers ask, and where the message goes back to them.
- A back-in-stock app, if you already use one. If it has a public API, AeroChat can add chat requests to the same list.
Questions
Can AeroChat tell customers when an item will be back?
Only if you add the date to its knowledge. Otherwise it says it’s sold out and offers the back-in-stock message.
Do I need a WhatsApp template for the restock message?
Yes, when it is sent outside the 24-hour customer service window. See WhatsApp message templates.
Can I see how many people are waiting for an item?
Yes. Filter your AeroChat contacts by the waitlist tag. That count is real demand for your next order from the supplier.
Does this work for items that will never return?
Mark them as discontinued in your knowledge base, and AeroChat will suggest alternatives instead of offering a waitlist. See also stock and back-in-stock questions.
Using a different system? If it has a public API, it connects to AeroChat the same way: describe what you want, paste in its key, and it runs.
Can’t find your tool? Message us in the chat on this page and we’ll tell you how it connects.
Keep the sale when an item sells out
Install AeroChat, paste the waitlist recipe, and ask your own store chat for a sold-out size.
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