Low-stock threshold: how to calibrate without false positives

Low-stock thresholds are one of the highest-leverage, lowest-effort improvements an e-commerce team can make. One afternoon of calibration prevents weeks of stockouts per year. The problem is that most teams set one global threshold and wonder why alerts are either constant or useless.

1. The formula

The correct low-stock threshold for any product is:

Threshold = (Average daily sales × Supplier lead time in days) + Safety stock

Where safety stock = (Max daily sales − Average daily sales) × Lead time.

Example: a product selling 10 units/day on average (max 16) with a 14-day lead time:

• Lead-time demand: 10 × 14 = 140 units
• Safety stock: (16 − 10) × 14 = 84 units
• Threshold: 140 + 84 = 224 units

This means you need to reorder when you have 224 units left — not when you hit zero.

2. The most common calibration mistakes

3. Setting up thresholds in Shopify

Shopify does not support per-variant low-stock thresholds natively in the admin. You can:

• Use Shopify Flow (Shopify Plus) to trigger alerts when stock drops below a product-specific value.
• Use a third-party app that reads variant stock and compares it to a custom metafield threshold.
• Use Seegea: define a threshold column per product and filter the catalog grid by stock below threshold.

4. Setting up thresholds in PrestaShop

PrestaShop has a native "Out of stock" action setting per product. For low-stock alerts before zero:

• Advanced Stock Management module: supports minimum stock quantity per combination.
• Email alert modules: available in the PrestaShop Addons marketplace.
• Seegea: custom threshold column, filter by stock below threshold, flag in grid.

Created in France (Annecy-Chantilly)

Seegea is a catalog editing layer for Shopify and PrestaShop. Threshold management is one of the first things new users set up — it takes 20 minutes and immediately reduces the noise from low-quality alerts. Shopify and PrestaShop only.