Shopify Inventory Management: Avoid Stockouts and Overstock

Inventory Problems Are Revenue Problems

Stockouts cost sales and frustrate customers. Overstock ties up cash in slow-moving products and creates storage costs. Getting inventory management right is one of the most impactful operational improvements a Shopify store can make — and it’s one that directly affects both revenue and profit margin simultaneously.

Key Inventory Management Concepts

• Reorder point — the inventory level at which you trigger a new purchase order. Formula: (average daily sales × supplier lead time) + safety stock.
• Safety stock — buffer inventory held to account for demand spikes or supplier delays. Typically 20–30% of your lead time demand.
• Days of stock on hand (DSH) — current inventory ÷ average daily sales. If DSH drops below your supplier lead time, you risk a stockout.
• Sell-through rate — units sold ÷ units received × 100. Low sell-through = overstock; targets vary by category (fashion: 80%+, perishables: 95%+).

Shopify Native Inventory Tools

Shopify’s built-in inventory management tracks stock levels, allows manual adjustments, generates low-stock reports, and supports multiple locations. It’s adequate for stores with fewer than 50 SKUs and single-location fulfilment. Enable inventory tracking on every product: Shopify Admin → Products → [Product] → Inventory → Track quantity.

Inventory Management Apps for Scaling Stores

• Stocky (free, by Shopify) — purchase order management, supplier tracking, inventory forecasting. Good starting point for growing stores.
• Cin7 — comprehensive inventory and order management, connects to 3PLs, marketplaces, and Shopify. For stores with complex multi-channel inventory needs.
• DEAR Inventory — manufacturing and inventory management. Good for brands that manufacture or assemble products.
• Linnworks — multi-channel inventory (Amazon + eBay + Shopify + others) from a single dashboard.

Demand Forecasting for Shopify

Basic demand forecasting: plot monthly sales for each SKU over the past 12 months. Identify seasonality (does this product spike in December? Summer?). Apply a growth factor based on your recent revenue trajectory. Build in buffer for promotional events (BFCM, seasonal sales). Review and adjust quarterly — forecasts are wrong until proven otherwise, and the goal is to be less wrong over time.

Need inventory management help for your Shopify store? Our operations team sets up inventory systems for scaling brands. Get in touch or view our operations work.