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  • OpenCart
  • Sales and conversion
  • v1.1.3

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

A subscription form for an out-of-stock product, and an auto e-mail to the buyer as soon as it's back. Subscriber list and demand report — what to restock first.

Download Free
Pro · lifetime licence The more sites, the less each one costs
Compatibility
OpenCart 2.3.0.x, 3.0.2 – 3.0.5.0 and 4.0.2 – 4.1.x
Version
v1.1.3 (OpenCart 4)
v1.1.2 (OpenCart 3.x)
v1.0.2 (OpenCart 2.3)
Licence
two sites, lifetime
Trial
7 days, no card, one per site
Updated
26 October 2026
Or all 173 Pro modules with All Access — 4 990 ₴ / year

The module in action — 48 sec

Clear even without sound: Ukrainian subtitles

What Free has,
and what Pro adds

The free version works with no time limit. Pro adds the rest of the features in the table.

Feature Free Pro
Subscription form instead of the "Buy" button on out-of-stock products ✔ ✔
Automatic e-mail when a product is back in stock ✔ ✔
Fires on manual changes, on imports, and on API updates alike ✔ ✔
Bot protection and a per-address subscription limit ✔ ✔
One-click unsubscribe via a link ✔ ✔
Demand report: how many people are waiting for each product ✔ ✔
Up to 25 active subscriptions in the free version, unlimited in Pro ✔ ✔
Telegram notifications — ✔
E-mail subscription confirmation, double opt-in — ✔
E-mail templates with placeholders, in both languages — ✔
Export subscriptions to CSV — ✔

What it looks like

On a product with no stock, the “Buy” button is replaced with a subscription form. The button can also stay in place, with the form shown below it.
Module settings on the free tier: Pro features shown greyed out
Free version. Pro features aren’t hidden — they’re in place, greyed out, with a badge and an explanation of what they give you.
Subscriber list with filters by product, e-mail, status and date
Subscriber list: statuses, dates, bulk actions. CSV export is a Pro feature.

Key points

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.

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).

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.

The trial starts when you ask

A fresh install is the free version, nothing switches on by itself. The “Try Pro for 7 days” button → e-mail → the key right in the window and by e-mail.

One key — two sites

Moving the store? Unbind the licence on the old domain and activate it on the new one yourself. For studios — keys for 5 or 25 sites, or unlimited.

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.

Version history

v1.1.2 OC 3.x v1.0.2 OC 2.3 Current 26 October 2026

A purchased licence for OpenCart now works without expiry.

v1.1.3 OC 4.x 26.09.2026

The subscription list with a filter opens again on the PDO database driver.

v1.1.2 OC 4.x) · 1.1.1 (OpenCart 3.x) · 1.0.1 (OpenCart 2.3

The “confirm subscription” and “unsubscribe” links no longer fire for an e-mail scanner.

All versions (7)
v1.1.1 OC 4.x

A purchased OpenCart licence works with no time limit.

v1.1.0

Pro unlocks with a key, and the trial only starts on the owner’s own click.

v1.1.0 OC 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, the trial is only issued on your own click.

v1.0.0 OC 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.

Frequently bought with Notify me when available

4 modules in one order — 40% cheaper than separately

“Store starter” bundle Notify me when available Nova Poshta Premium LiqPay Telegram notifications and Viber/SMS for customers Need more — all 173 modules in All Access for 4 990 ₴.
3 790 ₴ lifetime instead of 6 260 UAH bought separately
Buy the bundle →

Full module description

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 for each store language, 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

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 7-day key.

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.

Under the hood

A manual stock change in the admin is caught immediately, by a product model event. A price list import, an exchange with an accounting system or a direct database edit is picked up by a regular cron pass that checks who is waiting for a product that is in stock right now. On OpenCart 4 this job is registered under Cron Jobs automatically; on 3.x and 2.3 the cron link from the module settings has to be added on your hosting.

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.

Questions
about the module

Didn't find the answer? Message us on Telegram and we'll reply within a business day.

@catcode_support Setup, compatibility, activation
Will the notification fire if stock is updated by a price list import?

Yes. The module doesn't depend on the product-save event and regularly checks which products have become available.

Will a buyer get several e-mails about one product?

No. The subscription closes right after the e-mail is sent.

How does a buyer unsubscribe?

With one click on a personal link in the e-mail.

Can I see which product is most awaited?

Yes, a separate screen shows the subscription count per product — a ready-made demand report.

Is the form protected from spam?

Yes: a hidden field, a fill-time check, a per-address limit, and optional e-mail confirmation.

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