Low Stock Alerts for Customers on Shopify

To show customers a low stock alert on Shopify, turn on inventory tracking for the product, then add a low stock message with your theme’s inventory block or an app. Set an alert level so the message appears only when stock is really low, such as “Only 3 left in stock!”, and place it near the add to cart button.

This guide is about what shoppers see on your store, not reorder notifications for you. It covers your options, setup with a theme and with an app, how to choose the alert level, and how to keep the number honest. For how stock alerts fit with reviews, sales popups and timers, see our social proof guide for Shopify.

What is a low stock alert for customers?

It’s a short message on the product page that tells shoppers how many units are left once stock drops below a level you choose. “Only 2 left in stock!” or “Low stock: 4 left” are typical.

It does two jobs. It warns shoppers that waiting has a real cost, and it answers a practical question: “Will this still be here if I come back next week?” Both only work when the number is your real inventory.

What are your options on Shopify?

You have three routes. All of them need Shopify to track the product’s inventory first.

Step zero: turn on Track quantity

A low stock message can only count what Shopify counts. In Shopify admin, open Products, click the product (and the variant, if it has variants), turn on Track quantity in the Inventory section, enter the Available units and save (Shopify Help Center).

In the same section, check Sell when out of stock. By default, products stop selling at zero. If you choose Continue selling when out of stock, shoppers can keep buying after zero, which changes what “only 3 left” means. More on that below.

How do you show “Only X left in stock” with your theme?

Check your theme first. Shopify’s free Dawn theme has an inventory block for the product page. Its settings include an inventory threshold (0 to 100, default 10) and an option to show the quantity (Dawn source).

When the selected variant is at or below the threshold, the block shows “Low stock: X left” with an orange icon. Above it, the block shows “X in stock” or “In stock” (Dawn text). The block stays hidden for variants that Shopify doesn’t track.

To add it:

1. Go to Online Store > Themes > Customize and open a product template.
2. In the product information section, add the inventory block and drag it near the buy buttons.
3. Set the threshold and choose whether to show the number.
4. Save, then open a product with low stock to check it.

Theme blocks differ, so names and options may vary in your theme. The limits are similar in most: one threshold for every product, one fixed message, and no control over design or timing. If you need more than that, use an app.

How do you set up a low stock alert with Sam FOMO?

Here is the setup with Sam FOMO, our sales popup and urgency app. It is free to install and rated 4.6★ from 17 reviews on the Shopify App Store (Oct 2026). Its Low Stock Alert reads your Shopify inventory and appears once stock is at or below the level you set.

Step 1: Install the app and turn on the app embed

Install Sam FOMO and open it. In the Setup guide on the app home, click Enable. The theme editor opens on App embeds with Sam Boost Sales switched on. Click Save, go back to the app and check that the app embed shows Active. The install guide shows each screen. App embeds run on top of your theme, so they work with any theme version (Shopify Help Center).

Step 2: Create a Low Stock Alert

Open Notifications, click Create notification, pick Low Stock Alert and click Add. See create a notification if you haven’t used the editor yet.

Step 3: Write the message

The default message reads “Only {{stock_count}} items left in stock!”. You can insert three variables:

• {{stock_count}}: the number of units left.
• {{product_name}}: the product title.
• {{variant}}: the variant, such as a size or color.

Step 4: Set the Low stock alert level

Enter a number in Low stock alert level. The alert shows when stock is at or below it. The next section covers how to choose it.

Step 5: Choose the design, pages and timing

The alert counts the product a shopper is viewing, so set Show on under Placement to product pages. Pick a corner that doesn’t cover the add to cart button, especially on phones. You can set a separate mobile position under More placement options.

Under Design, pick a template (Classic, Trust Badge, Dark Mode or Urgency) or tick Match store style. Under Timing, set the delay before it appears and how long it stays. The design, placement and timing guide covers every option, and the low stock section shows the editor.

Step 6: Save and test with a real low-stock product

Click Save. Open a product whose stock is below your level in a private window and check that the count matches Shopify admin. Then open a product above the level and confirm no alert shows.

What alert level should you set?

Set it to a number that is really low for the products it covers. There is no right number for every store. Think about how fast each product sells and how soon you can restock.

These levels are examples, not benchmarks. A quick test: browse your store for a minute. If most products show the alert, your level is too high and shoppers will stop believing it.

Sam FOMO has one alert level per Low Stock Alert notification. If you need different levels for different product types, keep the level conservative, or use the theme block for a plain line and the app for a stronger alert.

How should you word a low stock message?

Short, specific and true. A count beats a vague warning, because shoppers can see you aren’t guessing.

• “Only {{stock_count}} left in stock!”: the default, clear on any product.
• “{{product_name}}, {{variant}}: only {{stock_count}} left”: for products where one size or color sells out first.
• “Only {{stock_count}} left from this batch”: for small-batch products you restock in runs.
• “Last {{stock_count}} at this price”: only if the price really changes when they sell out.

Skip phrases you can’t back up, like “selling fast” on an item that sold two units this month. If you sell in other languages, fill in Translations so the count reads naturally for every shopper.

When is a low stock message misleading?

When the number isn’t your real inventory, or when “low” stock isn’t really limited.

Researchers who crawled about 11,000 shopping sites found 632 low-stock messages. They confirmed 17 deceptive ones on 17 sites: 16 lowered the count on a fixed schedule, and one generated random stock values on each page load (Mathur et al., CSCW 2019). Shoppers who refresh a page and see the number change on its own learn to distrust the whole store.

In the US, the FTC Act lets the FTC act against “unfair or deceptive acts or practices in or affecting commerce” (FTC). A stock count you made up tells shoppers something false. Shopify’s App Store rules also require apps to use only factual information and name false purchase notifications as falsified data (Shopify).

Watch for these less obvious cases too:

• You keep selling after zero. If Continue selling when out of stock is on and you restock on demand, “only 2 left” isn’t really scarce. Turn the alert off for those products, or say “2 ready to ship”.
• Stock split across channels. If you hold units back for wholesale or another channel, the count shoppers see should match what they can actually buy.
• Stale counts. If you update inventory by hand once a week, the number drifts. Sync it before you rely on the alert.

We cover fake activity data in more detail in are recent sales popups fake?, and honest scarcity examples in FOMO marketing examples.

What mistakes should you avoid?

• Forgetting Track quantity. No tracked stock, no count. It’s the first thing to check when nothing shows.
• An alert level that’s too high. “Only 48 left” isn’t low stock. It reads as a sales tactic.
• Too much urgency on one screen. A low stock alert, a countdown, a visitor count and an email popup at once feels like pressure. Pair the alert with one other signal at most.
• Covering the buy button. Test on a phone. If the alert sits over add to cart, move the corner or the mobile position.
• Never checking the numbers. Sam FOMO’s Analytics shows impressions and clicks by popup type (analytics guide). Compare conversion on low-stock products in similar periods with and without the alert, and keep what helps.

If you run a real sale on limited stock, a countdown timer for the sale’s end date and a low stock alert for the item can work together. Just make sure both the deadline and the count are true.