The Complete Guide to Shopify Inventory Management

Shopify inventory management covers everything from tracking stock levels and setting reorder points to forecasting demand and avoiding stockouts. For DTC brands handling 100–2,000 SKUs, getting this right is the difference between smooth operations and a cascade of refunds, angry customers, and dead capital tied up in the wrong products.

This guide breaks down how Shopify's native tools work, where they fall short, and what to layer on top to actually stay ahead of your inventory.

---

What Does Shopify's Built-In Inventory Management Actually Do?

Shopify's native inventory tools are solid for basics: you can track stock levels per variant, set inventory to be tracked per location, receive purchase orders, and run inventory counts. Here's what you actually get out of the box:

• Stock tracking per variant: Enable tracking on any product variant and Shopify will decrement inventory automatically when orders come in.
• Multi-location support: Assign inventory to up to 1,000 locations (stores, warehouses, 3PLs) and route fulfillment accordingly.
• Purchase orders and transfers: Create POs to receive new stock and transfers to move inventory between locations.
• Inventory adjustments: Manually correct counts with a reason code (damaged, returned, etc.) for an audit trail.
• Basic reporting: See inventory value, sell-through rates, and ABC analysis on higher-tier Shopify plans.

Where Shopify falls short is anything predictive. There's no native reorder point calculation, no low stock alert system that emails you, and no demand forecasting built in. You'll know you're out of stock — after the fact. That's the gap most growing DTC brands hit around the 200-SKU mark.

---

How to Enable Inventory Tracking on Shopify

Enabling tracking takes under a minute, but it's a step many new merchants skip, which leads to overselling.

1. Go to Products in your Shopify admin and open a product.
2. Scroll to the Inventory section on the product detail page.
3. Check Track quantity.
4. Set the current stock quantity for each variant.
5. Decide whether to allow customers to purchase when out of stock (usually leave this off unless you're doing pre-orders intentionally).

For stores with hundreds of SKUs, you can bulk-enable tracking via CSV export/import. Export your product catalog, set the Variant Inventory Tracker column to shopify and Variant Inventory Policy to deny, then reimport. Tools like Hextom: Bulk Product Edit ($9.99/mo) make this even faster if you need filtering and conditional edits across large catalogs.

Once tracking is live, your inventory quantities will update automatically with each sale, refund, and fulfillment.

---

What Is a Reorder Point and How Do You Calculate It?

A reorder point (ROP) is the inventory level that triggers a replenishment order. Hit this number, and it's time to buy more — not when you hit zero.

The formula:

Reorder Point = (Average Daily Sales × Lead Time in Days) + Safety Stock

For example: if you sell 15 units/day on average, your supplier takes 10 days to deliver, and you want 3 days of safety stock buffer:

ROP = (15 × 10) + (15 × 3) = 150 + 45 = 195 units

When your stock drops to 195 units, place the order. By the time it arrives, you'll have roughly 45 units left — your buffer against a spike in demand or a delayed shipment.

The tricky part is keeping these calculations current. Your sell rate changes with seasons, promotions, and channel mix. A static reorder point set in January is probably wrong by April. This is why automated tools that track sell rate dynamically matter more as your catalog grows.

---

How Shopify Inventory Locations Work

Shopify's inventory locations system lets you assign stock to specific physical or virtual locations — a retail store, a warehouse, a 3PL. Each location holds its own quantity, and Shopify's fulfillment logic (or your 3PL's) decides which location ships each order.

A few things worth knowing:

• Location-level tracking: You can have 50 units at your warehouse and 10 at a pop-up store. These are tracked independently.
• Available vs. committed: Shopify distinguishes between on hand, committed (in open orders), unavailable, and available inventory. Available = on hand minus committed.
• Inventory transfers: Moving stock between locations creates a transfer record, which you can receive against when the goods arrive.

For single-location DTC brands (which covers most sub-$5M Shopify stores), this is mostly set-and-forget. Where it gets complex is if you're split between a 3PL and a retail location — keeping counts accurate across both requires disciplined receiving processes or a dedicated WMS.

---

The Biggest Inventory Mistakes DTC Brands Make

1. No low stock alerts

Discovering a stockout via a customer complaint or a zeroed-out collection page is painful and avoidable. Most brands at 50+ SKUs need automated alerts — something that catches a product heading toward zero before it gets there.

2. Setting static reorder points

Your Q4 sell rate isn't your Q2 sell rate. If you set a reorder point once and forget it, you'll either overstock slow movers or blow through inventory on your best sellers.

3. Not accounting for lead time variance

Suppliers don't always deliver on time. If your average lead time is 14 days but your worst case is 21, your reorder point calculation should use the 21-day figure (or at minimum add a buffer).

4. Over-relying on Shopify's reports

Shopify's built-in reports show you where you've been. They don't tell you how many days of stock you have left or when you'll hit zero at current sell rates. That's the operational intelligence most brands are missing.

5. Buying based on gut feel

For a store doing 500 orders/month across 300 SKUs, intuition doesn't scale. You need data: sell rate per SKU, days of stock remaining, seasonal uplift multipliers. Without it, you end up with three months of inventory for a slow mover and none of your best seller.

---

Which Shopify Inventory App Should You Use?

The right tool depends on your complexity, budget, and what problem you're actually solving. Here's an honest breakdown:

If you just need low stock alerts and basic forecasting — the field is crowded with options in the $3–$30/mo range. Bee Low Stock Alert & Forecast ($5.99/mo) is a solid entry point with dynamic thresholds and reorder quantity calculations. iAlert ($2.99/mo) is the cheapest but has had reported customer support issues. LSA Low Stock Alert ($5.99/mo) offers daily email digests but has had reliability complaints.

If you want forecasting plus purchase order management — Prediko (from $49/mo) is the most capable in this tier with AI-driven forecasting and solid reviews (4.9★ from 190 users), though it takes time to learn. Fabrikatör (from $79/mo) automates PO creation but is priced for brands that have already scaled.

If you're managing 100–2,000 SKUs and want actionable alerts without enterprise complexity — Alertr (getalertr.com) is built specifically for this tier. It tracks sell rates per SKU, calculates days of stock remaining, sends low stock alerts via email or Slack, and helps you set intelligent reorder points. The free tier covers up to 50 SKUs; Pro is $29/mo (currently $19/mo locked in at beta pricing). If you're running Slack-first operations, the Slack integration is particularly useful — alerts land where your team already lives.

If you need multi-location, manufacturing, or full ERP features — Katana ($299/mo) and Inventory Planner by Sage handle that complexity, but expect pricing and setup to match.

---

How to Set Up a Working Inventory System on Shopify (Step by Step)

This is the setup that works for most single-location DTC brands:

Step 1: Enable tracking on all products Use CSV bulk import or Hextom to enable tracking across your catalog. Set accurate opening quantities.

Step 2: Calculate reorder points for your top 20% of SKUs Use the formula above. Your top sellers cause the most pain when they stock out — start there.

Step 3: Set up low stock alerts Whether you use Alertr, Bee, or iAlert, get something in place that emails or Slacks you when inventory hits your reorder point. Don't rely on manually checking the Shopify admin.

Step 4: Document your lead times For each supplier, record average and worst-case lead times. Feed this into your reorder point calculations.

Step 5: Run a weekly inventory review Pull a report — ideally sorted by days of stock remaining — every Monday. Identify anything under 14 days and act on it. This meeting should take 20 minutes, not two hours.

Step 6: Reconcile counts monthly Spot-check physical counts against Shopify's records for your top SKUs. Inventory shrinkage, receiving errors, and return discrepancies add up.

---

Should You Use Shopify's Native Tools or a Third-Party App?

For stores under 50 SKUs doing under $500K/year, Shopify's native tools are probably enough — especially with manual reorder tracking in a spreadsheet. Above that threshold, the math changes.

At 200 SKUs, manually checking stock levels is a part-time job. At 500 SKUs, it's impossible to do well. The ROI on a $19–$49/mo inventory app is immediate if it prevents even one significant stockout per month on a mid-volume product.

The honest answer: use Shopify's native tools as the foundation (they're genuinely good), and layer a specialized app on top for alerts, forecasting, and reorder intelligence.

---

Inventory management doesn't need to be complicated — it needs to be consistent. Get the alerts, keep the math current, and review weekly.

If you're ready to stop discovering stockouts after the fact, Alertr's free tier covers up to 50 SKUs with no commitment. For growing brands, the Pro plan at $19/mo (beta pricing, locked in forever) gives you sell rate tracking, days of stock estimates, configurable thresholds, and Slack or email alerts — everything you need to stay ahead of your inventory.

---