“Out of stock” is the kiss of death for your conversion rate. At least that’s what you’d hear from our team.

A customer who’s ready to buy right now isn’t going to wait around. They’re bouncing straight to your competitor. 

Bad news is that Shopify’s built-in tools won’t hold your hand through this. If you’re running a growing store, you need systems that actually tell you when the shelves are running bare. 

This guide covers everything from the scrappy DIY approach to full automation, so you can keep your products in stock and your customers happy.

Why Low Stock Alerts Are Non-Negotiable?

Think of inventory management as your store’s early warning system. Here’s what breaks when you don’t have one:

• You’re literally leaving money on the table. No stock, no sale. Pretty simple math.
• Google punishes you for it. Search engines notice when your pages are constantly out of stock. Plus, imagine burning ad budget paying for traffic to a sold-out page. Ouch.
• Your reputation takes a hit. Nothing destroys trust faster than delays, backorders, and “sorry, we’re out” emails.
• Your cash flow stays messy. Smart alerts let you practice just-in-time inventory. You only buy what you need when you need it.

The types of low-stock alerts you might want to set up

Here’s how our team thinks of Shopify stock alerts.

There isn’t one stock alert. You need to consider different types of alerts—from when your stock starts to dwindle to notifying customers when the product is back on the shelves.

This table can help you grasp the full picture:

How to Set Up Low-Stock Alerts for Your Inventory?

You can set up low-stock alerts in multiple ways. 

We’ll describe each, then you can decide which one fits your preferences well, depending on whether you’re a small store with minimal catalog, a huge marketplace, or something else.

Method 1: The “DIY” Manual Approach (Free)

If you’re running a small catalog, you can get by with Shopify’s built-in reports.

It’s not fancy, but it works.

Head to Analytics > Reports and dig into the Inventory section. Under Products > Inventory, sort by the “Available” column. Filter by product type or vendor to see what’s running low.

The reality check: This is free, sure. But it’s also a pain. You’ll forget to check, you’ll miss things, and once you hit 50+ SKUs, this becomes a full-time job nobody wants.

Method 2: Native Shopify Staff Notifications

Shopify’s got a basic notification system that’ll ping your team when inventory hits certain levels.

Go to Settings > Notifications > Staff Notifications. 

Under “Inventory,” flip on the low inventory alert toggle. You’ll get an email when a product variant hits zero.

Downside: It’s one-size-fits-all. You can’t say “alert me at 10 units for this bestseller, but 50 for that one.” It’s reactive, not proactive. By the time you get the email, you might already be toast.

Method 3: Shopify Flow (For Advanced & Plus Users)

If you’re on Shopify Plus (or have access to Flow), this is where things get interesting.

You can build custom automation logic.

• Set up a trigger based on “Inventory quantity changed.” 
• Add a condition like “if quantity drops below X units.” 
• Then choose an action—send an email, post to Slack, create a task in Asana, whatever works for your team.

Pro move: Use product tags to set different thresholds. High-volume items alert at 100 units. Limited-edition stuff alerts at 5. You’re running a business, not a guessing game.

Method 4: Third-Party Apps (The Gold Standard)

When you hit scale, alerts won’t be enough. You need intelligence. The right app doesn’t just tell you you’re low; it tells you exactly how much to reorder.

• Prediko: AI-powered forecasting that predicts demand 90 days out.
• Sumtracker: Perfect for multi-location setups. Real-time syncing across warehouses so you actually know what you have and where.
• Low Stock Alert (LSA): Lightweight and affordable. Does one thing really well: sends custom email and Slack alerts at whatever threshold you set.

Throughout our lifetime, we’ve used and written about a bunch of other inventory management apps that you can also check out.

The “Urgency” Strategy: Showing Low Stock to Customers

Let’s change the perspective a bit and stop looking at low stock as an operations problem only. 

It can also be a marketing opportunity.

If you’ve ever seen the “only 3 left” on a product page, you’ll know that it’s not an accident. That’s typical scarcity marketing that works because fear of missing out (FOMO) is real. 

Most modern Shopify themes have “Inventory Status” blocks you can add in the Theme Editor. Enable them. 

When shoppers see an item’s almost gone, it validates their choice and lights a fire under the “Add to Cart” button. 

Then your perfectly set up system will also notify your team that the same item is going out of stock, so you can refill it quickly. Pretty great.

Advanced Tip: Calculating Your “Reorder Point” (ROP)

Setting every alert to “5 units remaining” is lazy, and it’ll burn you. 

You need to do the actual math.

The formula: (Lead Time in Days × Average Daily Sales) + Safety Stock

Example: Your supplier takes 14 days to restock. You sell 10 units a day. That means you need to reorder at 140 units, not 5.

Safety Stock is your buffer for surprises—a sudden spike in sales, shipping delays, Mercury in retrograde, whatever.

Troubleshooting Common Issues

Ghost Inventory: Shopify says you have 5 units. Your warehouse says zero. This usually happens when returns aren’t logged correctly or your POS isn’t syncing.

Notification Fatigue: Getting 500 alerts a day? You’ll start ignoring them. Set up daily digest reports for low-priority items instead of real-time pings.

Negative Inventory: Make sure your settings don’t let customers buy what you don’t have—unless you’re deliberately running a pre-order strategy.

Alert, Restock, Repeat

Inventory management isn’t sexy, but it’s the difference between a profitable store and one that constantly disappoints customers. 

Here’s your homework:

Today: Check your top 10 bestsellers manually. Right now.

This Week: Set up at least one automated alert using Staff Notifications or Shopify Flow.

This Month: If you’re growing fast, test a forecasting app like Prediko or Sumtracker.

Key Takeaways:

• Track inventory at the variant level (size, color, etc.)
• Factor in lead times so you’re not scrambling
• Use low stock visibility on your site to create urgency

Run out of stock once, shame on your supplier.

Run out of stock constantly? That’s on you.

If you need help, in managing inventory at scale for your Shopify store, you can reach out to our founder Jack, and hop on a quick call. We’d strongly recommend it. Plus, it’s free.