How to Reduce Stockouts on Your Shopify Store

The Real Cost of Running Out

Research from IHL Group estimates that stockouts cost retailers nearly $1 trillion globally every year. For Shopify merchants, the impact is even more personal: a single out-of-stock bestseller can mean hundreds of dollars in lost revenue per day, negative reviews, and customers who never come back.

The good news? Most stockouts are preventable. They happen because of poor visibility, manual processes, and reactive ordering. Fix those, and you fix the problem.

1. Set Reorder Points for Every SKU

A reorder point is the inventory level at which you need to place a new order. The formula is simple: Reorder Point = (Average Daily Sales × Lead Time) + Safety Stock.

If you sell 10 units per day and your supplier takes 7 days to deliver, your reorder point is 70 units plus whatever safety buffer you want. Without reorder points, you’re guessing — and guessing leads to stockouts.

2. Track Lead Times by Supplier

Not all suppliers deliver at the same speed. Some ship in 3 days, others take 3 weeks. If you’re using the same lead time assumption for every product, you’re setting yourself up for surprises.

Maintain accurate lead times per supplier and update them based on actual delivery performance. StockrHub lets you store lead times on each supplier record and factors them into reorder calculations automatically.

3. Use Sales Velocity, Not Gut Feeling

“I think we sell a lot of these” is not a demand forecast. Look at actual sales data over 30, 60, and 90 day windows to understand how fast each product moves. Products with high velocity need more aggressive reorder points; slow movers can be ordered less frequently.

StockrHub’s demand forecasting engine calculates velocity automatically from your Shopify order history, so you always have current numbers to work with.

4. Set Up Low-Stock Alerts

Even with reorder points in place, things slip through the cracks. A sudden spike in orders, a delayed shipment, or a forgotten PO can catch you off guard.

Email alerts that fire when inventory drops below a threshold give you an early warning system. You can act before a product actually hits zero — which is always better than finding out from a customer complaint.

5. Keep Safety Stock for Your Top Sellers

Safety stock is extra inventory you hold as a buffer against demand variability and supply delays. Not every product needs it — focus on your top 20% of SKUs by revenue. These are the products where a stockout hurts the most.

A common formula: Safety Stock = (Max Daily Sales − Avg Daily Sales) × Max Lead Time. This gives you a cushion for worst-case scenarios without tying up too much capital in slow-moving inventory.

6. Automate Your Purchase Orders

Manual PO creation is slow and error-prone. By the time you notice a product is low, pull up a spreadsheet, calculate how much to order, and email your supplier, you’ve lost days.

Automated reorder suggestions — like StockrHub’s auto-reorder engine — monitor your inventory levels continuously and generate draft POs when products hit their reorder points. All you have to do is review and send.

Putting It All Together

Reducing stockouts isn’t about any single tactic. It’s about building a system: accurate data, clear thresholds, proactive alerts, and fast ordering. Each piece reinforces the others.

Start with your top 10 products. Set reorder points, verify supplier lead times, and turn on alerts. Once those are dialed in, expand to the rest of your catalog. You’ll be surprised how quickly the stockouts disappear.