WooCommerce inventory management typically relied on WooCommerce's built-in stock tracking plus plugins like ATUM or WooCommerce Advanced Notifications. On Shopify, the native inventory system is simpler but pairs well with dedicated apps and Shopify Flow automations. Here's how to set up a solid inventory management system from day one of your Shopify launch.

WooCommerce inventory management vs Shopify

Feature	WooCommerce	Shopify native
Stock tracking	Per product + per variation	Per variant, per location
Low stock threshold alerts	WooCommerce built-in emails	Shopify Flow or manual
Purchase orders	ATUM plugin	Shopify Inventory (Purchase Orders)
Inventory reports	WooCommerce reports or ATUM	Shopify Analytics: Inventory reports
Multi-location	Plugin required	Native multi-location inventory
Forecasting	ATUM or third-party	App required (Inventory Planner, Skubana)
Back-in-stock notifications	Plugin (YITH, Klaviyo)	App (Klaviyo, Wishlist Plus)
Supplier management	ATUM Suppliers or manual	Shopify Inventory Purchase Orders

Shopify native inventory features

Inventory tracking settings

Enable inventory tracking per variant: Product → Variant → Inventory → Track quantity
Continue selling when out of stock: enable for pre-orders or made-to-order products; disable for standard retail
Inventory policy: "Shopify tracks this product's inventory" — disable for services, digital products, or print-on-demand

Multi-location inventory

Add locations: Admin → Settings → Locations. Add each warehouse, retail location, or 3PL address.
Stock quantities are location-specific — important for accurate fulfillment routing
Inventory transfers: move stock between locations within Shopify Admin
Fulfillment priority: set which location fulfills orders first (Shipping and delivery → Fulfillment)

Purchase orders (Shopify Inventory)

Create purchase orders in Admin → Products → Inventory → Purchase Orders
Select supplier (add suppliers in Inventory), products, and quantities
Mark as received when stock arrives — inventory auto-adjusts
Export PO as PDF to send to supplier
Limitations: basic supplier management. No automatic reorder point triggering.

Setting up low-stock alerts with Shopify Flow

Shopify doesn't send native low-stock emails automatically. Use Shopify Flow (free) to build this automation:

Basic low-stock email flow

Trigger: Inventory quantity changed
Condition: Variant inventory quantity <= 5 (your threshold)
Action: Send email to owner — "Low stock: {product.title} ({variant.title}) — {inventory_quantity} remaining"

Advanced low-stock Slack notification

Trigger: Inventory quantity changed
Condition: Variant inventory quantity <= reorder_point (stored as metafield)
Action: Send HTTP request to Slack webhook
Body: {"text": "Reorder alert: {{product.title}} — {{variant.title}}: {{inventory_quantity}} remaining"}

Auto-tag low stock products

Trigger: Inventory quantity changed
Condition: inventory_quantity <= 3
Action: Add tag "low-stock" to product
(Use this tag in a collection: "Low Stock" collection for buyer urgency messaging)

Zero-stock product status change

Trigger: Inventory quantity changed
Condition: inventory_quantity = 0 AND all variants of product are 0
Action: Set product status to Draft (hides from storefront)

Reorder point metafields

Store per-product reorder points as metafields to enable intelligent alerting:

product.metafields.inventory.reorder_point (number_integer) — trigger reorder when stock hits this level
product.metafields.inventory.reorder_quantity (number_integer) — standard order quantity when reordering
product.metafields.inventory.lead_time_days (number_integer) — days from order to delivery from supplier
product.metafields.inventory.supplier_sku (single_line_text) — supplier's product code for PO generation
product.metafields.inventory.preferred_supplier (single_line_text) — supplier name for this product

Use Shopify Flow to read the metafield reorder point instead of a hardcoded number — this allows different thresholds per product without editing your automation.

Back-in-stock notifications for customers

When products go out of stock, capture customer demand via back-in-stock alerts:

Klaviyo Back in Stock

Integrates with Shopify inventory. When variant drops to zero, shows "Notify me" button.
When stock is restored, Klaviyo sends automated email to all waitlisted customers
Can segment waitlist by variant (color/size) — only notify customers who wanted the specific sold-out variant
Required setup: Klaviyo Back in Stock block on out-of-stock product page via theme liquid edit

Wishlist Plus / Swym Back in Stock

Alternative to Klaviyo — standalone back-in-stock app
Shows subscriber count for each out-of-stock product in Shopify Admin — useful for prioritizing which products to reorder first
Integration: add "Notify me" button to product template

Inventory forecasting apps

For stores needing predictive reordering (seasonal demand, growth planning), these apps integrate directly with Shopify:

Inventory Planner

Analyzes sales velocity per variant, adjusts for seasonality and trend
Generates purchase order recommendations: "Order 200 units of SKU-123 to cover 60 days"
Syncs directly to Shopify to create POs
Best for: established stores with 6+ months of sales history to train on

Skubana / Extensiv

Enterprise-grade multi-channel inventory management
Combines forecasting, 3PL management, multi-warehouse routing
Best for: high-volume stores with multiple warehouses or 3PL partnerships

Simple Inventory Planner (budget option)

Basic velocity-based forecasting
Export suggested reorder quantities to CSV for manual PO creation

Migrating inventory data from WooCommerce

What to migrate

Current stock quantities (included in WooCommerce product CSV export)
Reorder points and reorder quantities (if stored as custom fields in WooCommerce/ATUM)
Supplier information per product
Historical purchase orders (for forecasting context — export from ATUM or WooCommerce Order reports)

Import stock quantities to Shopify

Shopify product CSV: Variant Inventory Qty column sets initial stock on import
Inventory CSV (Admin → Products → Inventory → Export): separate CSV for updating existing variant quantities by location
For multi-location: Shopify Inventory CSV has a column per location — assign stock to the correct location during import

ABC inventory analysis post-migration

Use the first month on Shopify to perform an ABC analysis of your catalog:

A items: Top 10–20% of SKUs by revenue. Keep high stock, monitor daily, low reorder point.
B items: Mid-tier sellers. Standard reorder cycles.
C items: Low-velocity, long-tail SKUs. Minimal stock. Consider just-in-time ordering.
Shopify Analytics → Products → Sales by product: use this to identify A/B/C items in your new store
WooCommerce migrated products: supplement Shopify analytics with WooCommerce historical data for the first 90 days (forecasting needs history)

Inventory management migration checklist

Export stock quantities from WooCommerce CSV and import to Shopify product CSV
Configure multi-location inventory if using multiple warehouses or 3PL
Create reorder point metafields (reorder_point, reorder_quantity, lead_time_days)
Build Shopify Flow: low-stock alert email to warehouse team
Build Shopify Flow: auto-tag low-stock products for urgency messaging
Build Shopify Flow: auto-draft zero-stock products (if desired)
Install back-in-stock app (Klaviyo or Swym)
Add "Notify me" button to product page template for out-of-stock variants
Migrate supplier data to Shopify Inventory Suppliers
Set up purchase order workflow in Shopify Inventory
Evaluate and install forecasting app if store has 1,000+ SKUs or seasonal demand

The most impactful immediate action after migration is setting up the low-stock Shopify Flow with Slack or email notification. WooCommerce's built-in stock emails are easy to miss in a busy inbox. A Slack notification to a #restock channel that fires when any variant hits a configurable threshold is one of those operational improvements that saves real money — running out of a best-seller is significantly more costly than the hour it takes to set up the Flow.

Shopify inventory forecasting & restock alerts after WooCommerce (2026)