E-commerce
July 1, 2026
A stockout by size is frustrating because the product exists, but not in the option the customer needs. They want to know if the size is coming back, if they can take another size, be alerted, or choose a really close alternative.
The chatbot must explain the stock by variant, offer honest options, and avoid pushing an unsuitable size just to convert. It can help choose between waiting, trying another fit, taking an alternative, or requesting an exchange.
This guide shows how to manage stockouts by size with an AI chatbot, without turning an unavailability into a bad recommendation.
Summary
Why does a split by size require consulting?
The customer may be tempted to choose a size that is available by default. If it does not fit, the brand gets a return and the customer experiences disappointment.
The chatbot must therefore prioritize the right choice over the available choice. It must explain the alternatives without downplaying the sizing risk.
A size in stock is not a good alternative if it does not fit the customer.
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What information should be checked?
The bot must check the product, the desired size, the remaining sizes, the fit, the material, customer reviews, the restock timeframe, stock alerts, and close alternatives.
It must also ask if the customer has a deadline or if the product is intended as a gift, as this changes the advice given.
How do I suggest a similar size?
A neighboring size may be suitable if the cut, material, and customer preference allow. The chatbot must explain the trade-off: more fitted, looser, longer, or less structured.
It should not say "size up" without context. This quick response often leads to returns.
How to suggest a product alternative?
If the desired size is unavailable, the bot can suggest a similar model in the correct size, a close fit, a different color, a product from the same collection, or a stock alert.
It must explain what remains comparable and what is changing, notably the cut, the material, the price, or the return conditions.
How to manage alerts and pre-orders?
If a restock is planned, the chatbot can offer an alert or a pre-order. It must specify whether the date is estimated, confirmed, or unknown.
If no date exists, it is better to say so clearly and suggest realistic alternatives.
Which flow to follow?
The flow must avoid pushing a wrong size.
Identify product, desired size, usage, deadline, and fit preference.
Check stock by size, restocks, alerts, pre-orders, and alternatives.
Evaluate if a neighboring size is reasonable based on fit and fabric.
Offer waiting list, alert, alternative, different color, or different model.
Escalate restocking requests, volume orders, urgent exchanges, and critical sizes.
Which messages should be used?
For out of stock: "The desired size is unavailable for this option, I am checking the closest options."
For neighboring size: "The larger size may be suitable if you prefer a looser fit."
For alert: "I can notify you if this size becomes available again, but the restock date is not yet confirmed."
When to transfer?
The transfer is necessary if the customer requests a confirmed restock date, a reservation, an urgent exchange, a group order, or non-public stock information.
The bot must transmit the product, desired size, stock, proposed alternative, deadline, restock request, and urgency.
Which KPIs should be monitored?
Track out-of-stocks by size, alerts created, accepted alternatives, returns after neighboring size, replenishment requests, and sizing-related dropouts.
This data helps to better anticipate missing sizes and improve recommendations.
Which mistakes should be avoided?
Avoid pushing an available but unsuitable size, promising a restock, ignoring a deadline, or replacing a fit without explaining the difference.
The chatbot must preserve trust even when the ideal size is missing.
How can Qstomy help?
Qstomy can connect the chatbot to the catalog, variants, size guides, stock levels, SMS campaigns, social content, and support rules to answer clearly, then hand over sensitive cases with an actionable summary.
The chatbot helps the customer move forward without inventing a reference, size, availability, or promotion that has yet to be confirmed by a reliable source.
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Key takeaways
Key Takeaways
An out-of-stock situation by size must lead to a real alternative: alert, pre-order, neighboring size, or comparable model.
What the customer must understand
The customer must understand the risk of a different size and the limits of restocking.
The chatbot's correct limit
The chatbot can offer options, but it must transfer reservations, confirmed restocking, urgent exchanges, and bulk orders.
Enzo
July 1, 2026
