Notify me when available — product subscriptions for OpenCart 2.3, 3.x and 4.x

Notify me when available turns a visitor who left empty-handed into an order. If a product is out of stock, instead of a “Buy” button the buyer sees a subscription form — and once the product is back, they get an e-mail automatically.

A reliable trigger

This is the main difference from simple alternatives. The module doesn’t try to catch the “moment of change” in stock — it regularly checks which currently-purchasable products people are waiting for. So the notification fires correctly whether stock was changed by hand in the admin, updated by a price list import, updated via the API, or even edited directly in the database — the exact cases where modules relying only on the product-save event usually break.

Protection from junk subscriptions

The form is protected from bots with a hidden field and a fill-time check, subscriptions from one address are rate-limited per hour, and e-mail subscription confirmation can be switched on (Pro). Fields are filled in automatically for logged-in customers.

Notifications

The buyer gets an e-mail with the product name, the price in the currency they saw, a link to the product, and a one-click unsubscribe link. In Pro, e-mail templates can be edited in the admin in both languages, with placeholders, and Telegram notifications can be enabled too.

The subscriber list as a demand report

In the admin — a full subscription list with filters by product, e-mail, status and date, a manual “send now”, bulk delete and CSV export (Pro). A separate screen shows how many people are waiting for each product — a ready-made answer to what to order next.

Free version and Pro

Free: a subscription form on the product page, an automatic restock e-mail, a subscriber list with filters and bulk actions, a demand report, bot protection and a per-IP subscription limit, one-click unsubscribe, automatic cleanup of old entries. One limit only — up to 25 active subscriptions at a time.

Pro: no subscription limit, e-mail subscription confirmation (double opt-in), Telegram notifications for the owner, custom e-mail text for each store language, exporting subscriptions to CSV.

Trial — only on your click. A fresh install is a clean free version: nothing Pro switches on by itself or goes dark after a week. When you want to look at Pro, click “Try Pro”, enter your e-mail, and get a genuine 7-day key — the same one you’d get on purchase, just shorter.

Why a store needs this

A product runs out — and traffic to its page keeps coming, but turns into zero. A customer sees “out of stock” and goes to a competitor, and you never find out there was demand for that item.

The subscription form turns that zero into two assets: a deferred sale and data on real demand — exactly what to restock first.

How it works, step by step

1. On a product with no stock, a subscription form shows instead of the “Buy” button.

2. The buyer leaves an email; the module filters out junk subscriptions before recording them.

3. As soon as stock returns, the trigger fires and every subscriber to that item gets a notification.

4. The subscriber list in the admin works as a demand report — you see what people are missing most.

Pricing

A Pro licence is 1,290 UAH, per domain. The licence runs for a year: once it ends, the module keeps working, only updates and support stop.

Technical requirements

OpenCart 4.x, 3.x and 2.3 are supported, as well as ocStore builds based on them — three builds in one archive. The store needs working mail delivery.

Under the hood

The trigger is hung on the stock change in the model, not on saving a form in the admin. So notifications go out even when stock returns via a price list import or an exchange with an accounting system — the most common real-world scenario.

The core isn’t patched: everything runs through OpenCart’s standard events.

How to install

1. Upload the archive via “Extensions → Installer” and install the module.

2. Check that the form appeared instead of the “Buy” button on an out-of-stock product.

3. Subscribe yourself and restock the item — a notification should arrive.

4. If it doesn’t arrive, check the store’s mail settings — that’s the most common cause.

Version history

• 1.1.0 — Pro unlocks with a genuine key, and the trial only starts on the owner’s own click (previously 7-day Pro switched on by itself after installation and after every save). The licence is verified on the server, with a 14-day allowance if it’s unreachable. Fixed admin event handlers: on OpenCart 4.0.x they didn’t fire, so a product being restocked through the product form could go unnoticed. Fixed archive packaging — the previous build wasn’t accepted by the standard OpenCart Installer.
• 1.1.0 (OpenCart 3.x) — the 3.0.x build moved to the same model as 4.x and 2.3: the licence is verified on the CatCode server with a 14-day grace period, the trial is only issued on your own click (previously 7-day Pro switched on by itself after installation and after every settings save). Also fixed a bug where subscribing from the product page could fail with a server error.
• 1.0.0 (OpenCart 2.3) — a separate build for OpenCart 2.3.0.x: the same functionality, server-side licensing with a trial on click, compatible with PHP 5.6 and 7.0.
• 1.0.0 — first release.