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How Do I Tell Customers Their Size Is Back in Stock, Not Just That the Dress Is?

Fashion back-in-stock emails fire when any size returns, not the one shoppers wanted. We send size-specific alerts tied to real restocks and returns.

Updated 3 min readBy SpiderHunts Technologies

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Quick answer — TL;DR

Back-in-stock alerts go wrong in fashion when they watch the product rather than the size, or fire on a single returned unit that sells in minutes. We tie alerts to the size the shopper chose, send them in waves that match the stock actually available, and feed waitlist numbers into your reorder decisions.

'Good news, it's back!' (It was an XS)

Two hundred people signed up for a restock alert on your sold-out linen shirt. One customer returned an XS on Tuesday, the warehouse scanned it back to stock, and the alert fired to everyone. By lunchtime the XS had gone and a hundred and ninety-nine people had clicked through to find their size still sold out. Some of them emailed. A few unsubscribed.

It happens the other way too. A full restock of the shirt lands, and the alert fires to all two hundred at once. The medium sells out in twenty minutes and the people who opened the email an hour later are disappointed again.

Why alerts misfire

  • The sign-up form captures the product, not the size and colour.
  • Any stock change triggers the alert, including a single returned unit.
  • Everyone on the list is emailed at once regardless of how many units exist.
  • Waitlist numbers never reach the buyer planning the reorder.

Most alert apps can do better than this with the right settings, but they are usually installed on defaults on launch day and never revisited.

The quiet cost of a bad alert

What happensEffect
Alert fires for the wrong sizeShoppers learn to ignore your alerts
Everyone alerted for a few unitsMost people miss out, again
Returns trigger alertsYour list is burned on a unit that sells in minutes
Waitlist ignored in buyingPopular sizes under-ordered next time

A back-in-stock list is people telling you exactly what they want to buy. Using it badly wastes the most direct demand signal a fashion brand gets.

How we make alerts size-aware

  1. The sign-up asks for the colour and size, pre-filled from what the shopper already selected on the page.
  2. Alerts watch that exact variant. A restock of the medium only alerts people waiting for the medium.
  3. You set a minimum number of units before an alert goes out, so a single returned unit can be sold normally without emailing a waiting list.
  4. When stock does return, alerts go out in waves sized to the units available, earliest sign-ups first, with the next wave sent if stock remains.
  5. Alerts can go by email or text, depending on what the shopper chose and what your consent records allow.
  6. A weekly report shows waitlist counts per style, colour and size, along with open purchase orders, so the buyer can see where demand is ahead of what is coming.

How it plays out

The linen shirt restock arrives with forty mediums. The first wave emails the earliest medium sign-ups, roughly in line with the stock. An hour later, mediums remain, so a second wave goes. The XS return on Tuesday went back on sale quietly and was bought by someone browsing. Nobody got an alert for a size that did not exist.

In the buying meeting, the report shows that the waitlist for the shirt in a large is far longer than the open order. The buyer adds larges to the reorder while the factory can still change it.

Things we check along the way

Waitlists grow old. Someone who signed up in spring may not want the shirt in autumn, so very old sign-ups can be asked to confirm rather than simply emailed. Pre-order and back-in-stock can work together: when a size is on order but not landed, the page can offer a pre-order to people on the waitlist first, if you run pre-orders.

Colours matter as much as sizes. A shopper waiting for the olive medium does not want to hear that the black medium is back, so the alert names the exact colour and size and links straight to that variant with it already selected. If a colour is being discontinued rather than restocked, the people waiting for it can be told honestly and offered the nearest alternative, instead of waiting for an email that will never come.

Signs your alerts need fixing

  • Alert sign-ups do not capture size.
  • Customers complain the alert was for a size they did not want.
  • Single returned units trigger emails to everyone.
  • Restocks sell out before most of the list reads the email.
  • Buyers never see waitlist numbers when planning reorders.

FAQ

Frequently asked questions

The questions readers ask us after this guide.

Still have a question?

Ask us directly — a senior engineer will get back to you.

Ask about your project

Can our current alert app do this?

Some can, with settings changed. We check yours first and only build what it cannot do.

Do alerts need marketing consent?

An alert the shopper asked for is different from marketing, but the rules on consent are for you and your advisers. We build to whatever you decide and record consent properly.

What stops a returned unit triggering alerts?

A minimum stock threshold per variant that you set. Below it, the unit sells normally without an alert.

Can the waitlist feed our reorder spreadsheet?

Yes. The waitlist counts can be sent to a Google Sheet or your inventory system on a schedule.

What drives the cost?

Whether your existing app can be configured or needs replacing, how many channels send alerts and whether you want the buying report.

Keep reading

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