For Shopify stores with out-of-stock products, a restock alert app is often the first thing they consider. Back in Stock, with more than ten years of history, is one of the go-to apps. It is now offered under the name "Amp Back in Stock & Preorder +".
This article explains Back in Stock's key features, its pricing and the caveats worth knowing before you start, alongside screenshots.
What is Back in Stock?
Source: Shopify App Store, "Amp Back in Stock & Preorder +" (viewed November 2, 2026)
An app that prevents lost sales from stockouts with restock alerts and pre-orders
Back in Stock shows a "notify me when available" button on out-of-stock product pages and automatically notifies customers when the product is restocked. It has been on the Shopify App Store since 2011 and is said to be used by more than 25,000 brands. Its App Store rating is 4.9 (988 reviews as of November 2, 2026), and it carries the "Built for Shopify" badge.
| Item | Details |
|---|---|
| Provider | Amp (developer listed on the App Store as HEL SG PTE LTD, Singapore) |
| Alert channels | Email, SMS, web push |
| Main features | Restock alerts, pre-orders and presales, low-stock badges, wishlists |
| Dashboard language | English (App Store listing) |
| Pricing | Free up to 10 notifications a month; monthly pricing by notifications beyond that |
Back in Stock's key features
Restock alerts
Source: Shopify App Store listing images for "Amp Back in Stock & Preorder +"
Replace "sold out" with "notify me" to capture demand
You can show a "notify me when available" button and sign-up form, styled to match your store, on out-of-stock product pages. Customers register an email address or phone number, and when the product is restocked they are automatically notified by email, SMS or web push. Subscribers are unlimited on every plan, and you can also send follow-up notifications.
Pre-orders and presales
Source: Shopify App Store listing images for "Amp Back in Stock & Preorder +"
Take orders before stock arrives to secure sales early
You can show a "pre-order" button on products before stock arrives and take orders in advance. Besides full payment up front, it supports taking a partial payment first and charging the rest later. It helps with presales of new products and with not losing customers waiting for popular items.
Other features
- Low-stock badges: Show a badge on products with little stock left to encourage purchase
- Wishlists: Customers can save products they are interested in
- Demand insights: See how many restock requests each product has and use it for purchasing decisions
- Multi-language: Set button and notification text per language
- Integrations: Klaviyo and Mailchimp integration (Growth and above), API and webhooks (Pro)
Back in Stock pricing
Source: Shopify App Store, "Amp Back in Stock & Preorder +" (viewed November 2, 2026)
Pricing is based on the number of notifications you can send each month. Subscribers are unlimited on every plan.
| Plan | Per month (standard stores) | Per month (Shopify Plus) | Notifications/month |
|---|---|---|---|
| Free | $0 | $0 | 10 |
| Starter | $19 | $49 | 500 |
| Growth | $49 | $99 | 2,000 |
| Pro | $99 | $299 | Unlimited |
Paid plans come with a 14-day free trial. Pre-orders and SMS notifications are available from the Starter plan, and SMS is charged separately by destination country. Check the official listing for current amounts.
Back in Stock's strengths
- Polished for restock alerts: Customizable buttons and forms, follow-up notifications and everything else restock alerts need
- Pre-orders in the same app: Restock alerts and pre-orders/presales together
- Affordable to start: A free plan, and paid plans from $19/month
- Demand data for purchasing: See which products have the most restock requests to inform merchandising and purchasing
- Used by stores in Japan: The App Store includes reviews from stores in Japan
Caveats to know before using Back in Stock
The dashboard is mainly in English
According to its App Store listing, the dashboard supports English only. Customer-facing buttons and notifications can be set in Japanese, but the settings screens and help assume English.
More notifications mean a higher plan
Because pricing is based on monthly notifications, stores that restock popular items often or have many subscribers will need higher plans. Note also that Shopify Plus stores have separate pricing.
LINE is not a built-in channel
LINE, often used in Japanese ecommerce for restock alerts, is not one of its built-in channels. Some LINE integration apps can connect with Back in Stock to send restock alerts on LINE, so to use LINE you combine it with such an app.
Other CRM features need separate tools
Back in Stock is dedicated to restock alerts and pre-orders. For newsletters, segmented campaigns and automated journeys, you combine it with an email app or similar.
Stores Back in Stock suits
- Stores that only need restock alerts and want to start at low cost
- Stores that want to take pre-orders and presales in the same app
- Stores that already send email from another tool such as Klaviyo and only want to add restock alerts
- Stores with large catalogs that want to use restock demand data for purchasing
Summary
Back in Stock is a proven go-to app that is strong on restock alerts and pre-orders. You can try it for free, so starting restock alerts on the products that sell out most often is a good first step.
On the other hand, the English dashboard, pricing that rises with notifications and LINE not being a built-in channel are points stores in Japan should check before adopting it.
If you also want restock alerts on LINE: StoreCRM as an option
If you want to send restock alerts on LINE as well, or bring restock alerts together with email and LINE messaging, StoreCRM is another option. StoreCRM is a CRM app for Shopify stores in Japan that sends restock alerts by both email and LINE. Customers can link LINE from a button on the product page and sign up for the alert right there.
| Back in Stock | StoreCRM | |
|---|---|---|
| What it is | Dedicated restock alert and pre-order app | CRM (restock alerts are one feature) |
| Alert channels | Email, SMS, web push | Email, LINE |
| Price that includes restock alerts | From $19/month (free up to 10 a month) | From $100/month (Pro plan) |
See the StoreCRM pricing page or download our product guide for details on pricing and features.
References
- Amp Back in Stock & Preorder + (Shopify App Store)
- Back in Stock pricing page (Amp)
- CRM PLUS on LINE (Shopify App Store)
Information in this article is current as of November 2, 2026. Back in Stock's pricing and features may change.
