E-commerce
July 1, 2026
A stockout limited to a single size can be more frustrating than a complete stockout. The customer sees that the product is available, but not in the size they need. They wonder if a restock is coming, if they should choose another size, or look for an alternative.
Support must help them make a decision without pushing them toward a bad choice.
This guide shows how to handle customer questions about stockouts by size only.
Summary
Why does a size break cause so much frustration?
The customer has often already chosen the model, color, and price. Running out of stock in their size therefore comes as a final obstacle, sometimes at the moment of checkout or after a promotional campaign.
The response must offer a real follow-up, not just "unavailable".
When only a size is missing, support must help to choose between waiting, adapting, or replacing.
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What information should be checked?
Check requested size, variant, color, actual stock, replenishment, alert, equivalences, cut, returns, stores, marketplaces, cart, promotion, and customer urgency.
An alternative must take fit into account, not just stock.
How do you talk about restocking?
If a restocking date exists, provide a realistic window. If it does not exist, say so clearly and offer a stock alert or an alternative. The customer should not have to wait based on an uncertain promise.
Transparency prevents repeated follow-ups.
How do I suggest another size?
Do not automatically suggest the size above or below. First, explain the cut, the material, and customer reviews. If two sizes could fit, indicate the compromise between comfort and fit.
A size alternative must remain advice, not a way to clear out stock.
How to reduce disappointment?
Display the stock alert, close alternatives, available stores, and the option to be notified. If a promotion expires before restocking, explain whether the price can be maintained or not.
Support must report sizes that are frequently out of stock.
Out-of-stock situations become less frustrating if the customer keeps a clear option.
Support can also explain whether the out-of-stock situation affects only the online store or also physical stores and partners. This distinction is useful when the customer is willing to travel or purchase through another channel.
Availability must be readable by size, color, and channel.
Which flow to follow?
The flow must check stock and fit together.
Identify product, size, color, cart, urgency, promotion, and request.
Check stock, restock, alert, fit, equivalences, stores, exchange, and alternatives.
Explain availability, delay, options, and risk of choosing another size.
Create alert, suggest alternative, reserve, transfer, or document the request.
Measure stockouts by size, alerts, conversions, returns, exchanges, and satisfaction.
Which examples should be used?
“Size M does not have a restock date yet, but I can activate an alert.” “Size L can work if you are looking for a looser fit, but it will not replace the same fit.”
The answer must remain honest.
When to transfer?
Transfer is necessary for a VIP customer, high value, urgent event, uncertain restocking, exceptional reservation, expired promotion, or highly demanded critical size.
The bot must transmit the product, size, stock, cart, promotion, urgency, and risk.
Which KPIs should be monitored?
Track out-of-stocks by size, alert requests, alternative conversions, exchanges, returns, lost sales, and satisfaction.
This data improves purchasing and inventory planning.
Which mistakes should be avoided?
Avoid promising unconfirmed restock, pushing the wrong size, hiding an out-of-stock status at checkout, or forgetting the promotional impact.
Trust matters more than the immediate sale.
How can Qstomy help?
Qstomy can connect the chatbot to stocks, sizes, SMS campaigns, consents, codes, social networks, orders, offers, reviews, UGC, badges, warranties, and escalation procedures to respond accurately.
The chatbot helps the customer understand an out-of-stock situation by size, an SMS, a social purchase, a subscriber offer, or social proof without inventing a stock, discount, eligibility, proof, or promise that needs to be verified.
Explore AI support, the AI sales agent or request a demo.
Key takeaways
Key Takeaways
Out of stock by size should clarify stock, replenishment, alert, fit, alternative, promotion, reservation, and exchange.
What the customer needs to understand
The customer needs to know whether to wait, choose an alternative, or look for another product.
The chatbot's limits
The chatbot can check and advise, but it must transfer urgent matters, VIPs, reservations, and uncertain replenishments.
Enzo
July 1, 2026
