Running out of a frequently used item can interrupt a job or delay a sale. But ordering too early can leave cash tied up in stock that takes up valuable shelf space. A reorder point gives a small team a practical signal for when to start replenishing an item, based on how quickly it is used and how long a supplier takes to deliver.
What a reorder point tells you
A reorder point is the inventory level at which you should place a new order so that remaining stock can cover expected use while you wait for replenishment. The basic formula is: Reorder point = average daily usage × supplier lead time in days + safety stock. Lead-time demand covers what you expect to use before the next delivery is ready; safety stock is a separate buffer for unexpected demand or delay. The NC State Supply Chain Resource Cooperative’s tutorial explains how demand and lead-time variability affect the buffer you may need.
Work through one item by hand
Suppose a workshop uses an average of four rolls of packing material per day. Its supplier usually takes five days from order placement to delivery and put-away, and the owner chooses an illustrative six-roll buffer. Expected use during lead time is 4 × 5, or 20 rolls. Add the six-roll buffer and the reorder point is 26 rolls. The six-roll buffer here is an example decision, not a recommended universal amount; choose a buffer that fits the consequences of a shortage, supplier reliability, and available cash and space.
If the owner checks stock only once a week, the five-day supplier lead time is not the whole waiting period: the item may cross its trigger just after a check and sit for almost seven days before the next review. For a weekly review, include that review interval: review trigger = average daily usage × (supplier lead time + days between reviews) + safety stock. In this example, 4 × (5 + 7) + 6 gives 54 rolls. Use the appropriate method for your routine: a continuously monitored item can use the lead-time formula, while a periodically checked item needs coverage through the next review as well.
Use inventory position—not a misleading shelf count
Before comparing an item with its trigger, define what quantity you are measuring. For a simple manual system, inventory position means usable stock on hand plus confirmed incoming stock, minus quantities already committed or backordered. Do not count a delivery as both incoming and on hand, and do not treat damaged, quarantined, or expired goods as usable. For a reliable starting count, follow a verification routine such as the small-stockroom photo-to-inventory checklist; when deliveries arrive, the receiving checklist for short, damaged, or extra shipments can help you record what actually came in.
Set up a small, useful first pass
Start with a short list of important items that are used regularly, rather than trying to calculate a threshold for every object in the stockroom. Verify the count, then estimate average daily use from a representative period of sales or internal consumption. Keep units consistent: if usage is measured in cases, lead time and counts must refer to cases, or you need a clear conversion to individual units. For seasonal or one-off demand, avoid letting an unusual week silently become the new normal; record the reason and revisit the estimate when the pattern changes.
Next, measure supplier lead time from when the order is actually placed until the item is received, checked, and ready to use. Review past orders for the same item and supplier rather than relying only on a quoted delivery window. The QuickBooks guide to reorder-point calculations also highlights daily usage, delivery lead time, and safety stock as the key inputs. If delivery times or demand vary, a single average can hide risk; use a sensible, item-specific buffer, note how you chose it, and avoid copying one safety-stock number across unrelated products.
Keep the rule reviewable
Write down each item’s name, unit, supplier, usage estimate, lead time, buffer, calculated trigger, and date last checked. Review the inputs after a stockout, a late delivery, a sustained demand shift, or a repeated pattern of excess stock. Also separate the reorder point from the order quantity: the trigger answers when to replenish, while the order quantity answers how much to buy. Minimum order sizes, storage limits, cash availability, and supplier terms may affect that second decision.
A larger buffer can reduce the chance of running short, but it also ties up money and space; a smaller one can do the opposite. Treat the formula as a decision aid, not a guarantee, and adjust it as you learn. If you use Ququ Warehouses, the current Ququ homepage describes photo-based AI intake, bulk editing, and a warehouse list. Those are the stated inventory-list capabilities; this guide’s reorder calculation is a separate manual planning step, and it should not be assumed to trigger alerts or create purchase orders automatically.
