What it means
A shop sells its last few units of a popular item, and replenishment arranges more before the shelf stays empty, with stock coming from a supplier or another company location. Shopify describes replenishment methods such as reorder points and demand-based planning, and the method should fit demand and supplier reliability.
A fictional stationery store reviews notebooks each morning, moving stock from its back room to the sales floor and ordering more from the supplier when the warehouse balance falls, which are related but distinct replenishment steps. A reorder point signals when to place an order and often reflects expected demand during lead time plus safety stock, while the order quantity is a separate choice.
Oracle's reorder-point planning guidance accounts for lead time, demand and safety stock in its planning logic, and systems may also consider open orders and reservations, so check the definition of available inventory in the specific system. A fictional cafe sells 20 cartons a day and its supplier takes five days, so it may need at least 100 cartons to cover expected lead-time demand, plus a buffer for variation, which is a planning illustration, not a fixed universal rule.
The target stock level should cover the review cycle and lead time without creating waste, and for perishable goods shelf life can be more binding than storage capacity, while slow-moving items may call for smaller orders. An illustrative order quantity is target stock minus usable stock minus firm incoming stock, adjusted for committed demand, so if the target is 500, usable stock 180 and incoming stock 100, the simple gap is 220 units.
Check whether the incoming 100 will arrive before demand hits. Using inventory position can be more reliable than shelf count alone, as it includes stock on hand and on order, less backorders or allocations under the chosen method, and the components should be defined consistently.
A fictional electronics retailer has 40 phones in transit but 30 customer reservations while its screen shows 60 units on hand, and treating all 100 as freely available would hide a real shortage. Supplier lead time can vary, so use recent receipt data instead of only a quoted promise, with a safety buffer where delays or demand spikes are costly.
Replenishment can be automatic, but human review still matters, because promotions, product launches and supplier closures may not be in historical demand and should be flagged before the system repeats yesterday's pattern. A fictional pharmacy orders extra seasonal goods before a local demand peak and checks expiration dates and storage requirements, since the plan is not simply to maximise units on the shelf.
Stockouts can lose sales and trust while excess inventory ties up cash, incurs storage cost and may become obsolete, so the process balances both risks rather than eliminating one at any price. Track fill rate, stockout frequency, inventory turnover and waste by item or category, because averages can hide critical shortages, and keep the physical stock record accurate, since receiving errors, theft and misplaced items can make a good formula produce bad orders.
A fictional hardware chain transfers a fastener from a nearby store instead of placing an urgent supplier order after comparing transfer cost and expected lost sales, and minimum order quantities and case packs may force an order above the calculated gap, so the resulting overstock should be visible, not mistaken for demand. Collaboration with suppliers can improve availability, but a purchase order does not mean stock has arrived, and the policy should be revisited as demand changes; good replenishment means the right usable stock reaches the right place in time, resting on clean data, realistic lead times and regular exception review.
In practice
Real-world examples.
Example
A retailer orders stock when inventory reaches a reorder point of 130 units. The system checks inventory position, including open orders, before it raises the purchase order.
Example
A store moves units from the back room to an empty shelf each morning. No supplier order is needed, but the move is still a replenishment step that the manager tracks.
Example
A chain transfers stock from a nearby branch to avoid a shortage on a fast-selling item. It compares transfer cost with expected lost sales and chooses the transfer because the urgent supplier order would arrive too late.
Formula
Calculation
Order gap = target stock - usable stock on hand - firm incoming stock + committed demand not already reflected. Timing and pack sizes may change the order.
For example, suppose the target is 500 units, usable stock is 180, firm incoming stock is 100 and 30 units are committed to customers but not yet deducted. The gap is 500 - 180 - 100 + 30 = 250 units. If the supplier ships in cases of 24, the buyer rounds up to 11 cases, which is 11 x 24 = 264 units, and the 14 extra units should be visible as pack-size overstock rather than demand.
The reorder point for the same item can be found from demand during lead time plus safety stock. With daily demand of 20 units, a lead time of 5 days and safety stock of 30 units, the reorder point is 20 x 5 + 30 = 130 units, so an order is triggered when inventory position falls to 130.Case study
Seen in the real world.
In this fictional case, Lark Office Supply reviews a popular pen weekly. Its buyer checks current stock, confirmed incoming cases and expected demand before the next receipt. A promotion changes the usual sales rate, so the buyer adjusts the target temporarily. After the event, the team checks whether the extra stock sold.
Watch out
Common mistakes.
- Ordering from shelf count while ignoring stock already due.
- Using average lead time when supplier delays vary widely.
- Keeping an old target despite demand or shelf-life changes.
Questions
People also ask.
Is replenishment only a supplier order?
No. It also includes internal movement to the needed location.
What is a reorder point?
A stock threshold that signals when to order under a defined policy.
Why use safety stock?
It can buffer variation in demand or supply, at a carrying cost.
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