Demand Plan: Definition and Shopify Inventory Example

A demand plan estimates what products a merchant is likely to need, when they should reorder, and how much they should buy based on sales history, current stock, supplier lead times, and replenishment assumptions.

How Shopify merchants use Demand Plan

For Shopify merchants, a demand plan turns order history and inventory position into a forward-looking buying workflow. It helps teams decide which SKUs need purchase orders, which products are over-covered, and which supplier timelines create stockout risk.

What matters in practice

  • A demand plan connects sales velocity, on-hand inventory, supplier lead times, safety stock, and open purchase orders.
  • The output should be operational: reorder, hold, review, or create a purchase order.
  • Demand plans should be updated when promotions, seasonality, supplier delays, or new product launches change assumptions.

Why it matters

Common merchant pain points

  • Teams often have forecasts in one spreadsheet, supplier notes in another, and purchase orders somewhere else.
  • Without a demand plan, buying decisions can become reactive to low-stock alerts instead of proactive replenishment reviews.

Native Shopify limitations

  • Shopify stores inventory and order history, but it does not natively turn that data into a complete demand plan.
  • Merchants usually need an inventory planning app or spreadsheet model to connect sales velocity, lead times, and reorder quantities.

How to apply this in practice

  1. Step 1

    Start with demand history

    Review Shopify sales velocity by SKU and adjust for stockouts, promotions, and seasonality.

  2. Step 2

    Add supply constraints

    Layer in current stock, open purchase orders, supplier lead times, MOQs, and safety stock.

  3. Step 3

    Turn the plan into action

    Decide which SKUs need reorder recommendations, purchase orders, buying holds, or further review.

Examples

Monthly buying review

A merchant reviews demand, current stock, inbound inventory, and supplier lead times to decide which SKUs should become purchase orders this week.

Frequently asked questions

Related resources

Related guides

Related calculators

Related glossary terms

  • Reorder Point (ROP)

    Reorder point is the inventory level at which a new purchase order should be placed so that replenishment arrives before existing stock is depleted.

  • Safety Stock

    Safety stock is the extra inventory held above expected demand to reduce the risk of stockouts caused by variability in demand or lead times.

  • Inventory Turnover

    Inventory turnover measures how many times a company sells and replaces its inventory over a given period, typically a year.