How to Calculate Reorder Points for Retail Inventory

What is a reorder point?

A reorder point is the inventory level at which you should place a new order to replenish stock. When your stock count drops to this number, it triggers a reorder. The goal is to set the reorder point high enough that the new inventory arrives before you run out, but low enough that you are not tying up unnecessary capital in safety stock.

The basic formula is: Reorder Point = (Average Daily Sales × Lead Time in Days) + Safety Stock

For example, if you sell 10 units of cooking oil per day and your supplier takes 7 days to deliver, you need at least 70 units to cover the lead time. If you add 20 units of safety stock (to handle unexpected demand or delivery delays), your reorder point is 90 units. When stock drops to 90, it is time to order more.

In Vendrex, you set this number as the "Minimum Quantity" on each product or variant. When stock falls below this threshold, the product appears in your low stock alerts dashboard, letting you know it is time to create a purchase order.

Step 1: Calculate average daily sales

Your reorder point starts with understanding how fast each product sells. Guessing leads to either stockouts or overstock. Use actual sales data instead.

Look at 30-90 days of sales history. A week of data is not enough — it might include a weekend spike or a slow Tuesday that skews the average. Three months gives you a more reliable picture. In Vendrex, run a sales report by product to see units sold over any date range.

Calculate the daily average. Divide total units sold by the number of days. If you sold 300 units of a product over 30 days, your average daily sales is 10 units per day.

Adjust for seasonality. If the product sells faster during certain months (e.g., rice sells more before holidays), calculate a separate average for peak and off-peak periods. Use the higher number for your reorder point during peak season and adjust down afterward. For Haitian businesses, consider factors like harvest seasons (fresh produce from Kenscoff), school opening periods (uniforms, supplies), and holiday rushes (Christmas, New Year, Carnival).

Example for a grocery store in Delmas: A 5kg bag of rice sells 150 units per month on average. Daily sales = 150 / 30 = 5 units per day. During the December holiday season, sales jump to 300 units per month. Daily sales = 300 / 30 = 10 units per day. The reorder point needs to adjust between these two rates.

Step 2: Determine lead time

Lead time is the number of days between placing an order with your supplier and receiving the goods. This is not the same as the supplier's quoted delivery time — it includes processing time, payment clearing, shipping, customs clearance (for imported goods), and local transportation to your store.

For local suppliers: A produce supplier from Kenscoff might deliver within 2-3 days. A beverage distributor in Port-au-Prince might deliver within 5-7 days. Track actual delivery times for each supplier in your Vendrex supplier management system by noting the date each PO was placed and the date it was received. Over time, you will see patterns: which suppliers consistently deliver on time and which are always late.

For imported goods: Lead time for imported goods coming through the Port-au-Prince seaport can range from 3 to 8 weeks. The variability is high because of customs delays, port congestion, shipping schedule changes, and weather. For imported goods, use the longest realistic lead time rather than the optimistic one. If a shipment takes 4-6 weeks on average, use 6 weeks (42 days) as your lead time for reorder calculations. Being pleasantly surprised by an early arrival is better than running out of stock for two weeks.

Add a buffer for known delays. If your supplier is consistently 2-3 days late, add those days to the lead time. If the Port-au-Prince seaport is experiencing congestion (common during certain months), add an extra week. Your reorder point should reflect reality, not the ideal scenario.

Step 3: Calculate safety stock

Safety stock is the extra inventory you keep above the lead time coverage to handle uncertainty. Two types of uncertainty matter: demand spikes (more customers buy than usual) and supply delays (the supplier takes longer than expected).

A simple safety stock formula: Safety Stock = Average Daily Sales × Safety Stock Days. Safety stock days depend on how reliable your supplier is and how predictable your demand is:

Very reliable supplier, stable demand: 3-5 days of safety stock. Example: a local bread supplier who delivers every morning without fail.
Moderately reliable supplier, normal demand variability: 7-14 days of safety stock. Example: a beverage distributor who mostly delivers on time but occasionally misses a day.
Unreliable supplier or imported goods: 14-30 days of safety stock. Example: an overseas supplier shipping through the Port-au-Prince seaport where delays of 1-3 weeks are common.

Example using the rice calculation: Daily sales = 5 units (off-peak) or 10 units (peak). Lead time = 7 days (local distributor). Safety stock = 7 days (moderate reliability). Reorder point = (5 × 7) + (5 × 7) = 35 + 35 = 70 units off-peak. During peak: (10 × 7) + (10 × 7) = 70 + 70 = 140 units.

Step 4: Set reorder points in Vendrex

Once you have calculated the right reorder point for each product, enter it in Vendrex as the Minimum Quantity. Here is how:

Open the product detail page in Vendrex.
Navigate to the stock settings section.
Enter your calculated reorder point as the Minimum Quantity. For the rice example above, enter 70 (off-peak).
Optionally set a Maximum Quantity to prevent over-ordering. For the rice example, this might be 200 units (roughly one month of sales at peak).
Save. The system will now monitor this product and alert you when stock drops to 70.

For products with variants (different sizes, colors, or options), each variant has its own reorder point. A popular size like Medium in a clothing store might have a reorder point of 20, while size Small has 5. Set each one based on its own sales velocity.

For multi-store operations, each store location has its own stock levels and can have its own reorder points. The same product might have a reorder point of 50 at a high-volume store and 10 at a low-volume store. Each location receives its own alerts based on its unique thresholds.

Step 5: Use reorder points with low stock alerts and purchase orders

With reorder points set, Vendrex monitors every product automatically. When stock drops to the minimum, the product appears in the low stock filter in your product list and the dashboard shows the low stock count. You can then create a purchase order for the products that need replenishment:

Open the product list and enable the "Show Low Stock" filter. This shows only products at or below their reorder point.
Review each product's current stock level and reorder point to determine how much to order.
Create a purchase order for the supplier, adding the products and quantities you need. See purchase order management for detailed instructions.
When the goods arrive, receive the PO and inventory updates automatically.

This workflow connects your reorder point calculations to actual purchasing. You set the thresholds, the system highlights what needs attention, and you create POs for the products that are running low. Combined with supplier management for tracking supplier performance and pricing, this gives you a complete inventory replenishment system.

Common reorder point mistakes and how to avoid them

Using the same reorder point for all products. A best-selling item and a slow mover should not have the same threshold. Each product needs its own reorder point based on its unique sales velocity and lead time. Vendrex lets you set per-product minimum quantities so every product gets the right threshold.

Setting reorder points too low for imported goods. If a product takes 6 weeks to arrive (42 days) and you sell 10 units per day, you need 420 units just to cover lead time. A reorder point of 50 units will leave you out of stock for over a month. Match your reorder point to actual lead time, not your desired lead time. For imports through the Port-au-Prince seaport, always use the longest realistic lead time.

Ignoring seasonal demand changes. Reorder points that work in March will cause stockouts in December if demand doubles during the holiday season. Review your reorder points before peak seasons and adjust upward. Use Vendrex reports to compare sales by month and identify seasonal patterns.

Never updating reorder points. Sales patterns change. New competitors open. Supplier lead times fluctuate. Make it a habit to review reorder points quarterly. Products that used to sell 5 units per day might now sell 15. Update the minimum quantity in Vendrex to match current reality.

Setting and forgetting. A reorder point is not a one-time decision. It needs ongoing attention. Dedicate 30 minutes each month to reviewing your low stock alert history. Are certain products constantly triggering alerts? Raise their thresholds. Are some products never triggering alerts even though you want them to? Lower their thresholds. This monthly review keeps your replenishment system optimized.

Frequently Asked Questions

The reorder point is the total inventory level that triggers a reorder. It includes both the stock needed to cover lead time (lead time demand) and the extra stock kept as a buffer against uncertainty (safety stock). Safety stock is just the buffer portion. In the formula Reorder Point = Lead Time Demand + Safety Stock, safety stock is the second component that protects against demand spikes and supply delays.

At minimum, review reorder points quarterly. If your business experiences significant seasonal variation, review before each peak season. If a supplier changes their lead time or a product's sales velocity changes noticeably, update the reorder point immediately. Vendrex makes this easy — adjusting the Minimum Quantity on a product takes 10 seconds.

Yes. Each product variant can have its own minimum quantity. A t-shirt in size Medium might have a reorder point of 20, size Large 15, and size Small 5, based on their individual sales velocities. Each variant triggers its own alert independently. This per-variant precision ensures you never run out of a specific size while others remain in stock.

Yes. In multi-store setups, each store location can have its own minimum quantity for the same product. A high-volume store might have a reorder point of 50 while a low-volume store has 10. Each store receives its own low stock alerts based on its own threshold. This per-store flexibility ensures you reorder appropriately for each location's demand.

If you consistently have stock left over when the next order arrives, your reorder point may be too high (or you are ordering too much quantity). Review your low stock alert history. If a product rarely or never triggers alerts, consider lowering its threshold. The goal is to have stock arrive just before or just as you hit the reorder point. If stock arrives two weeks before you need it, you are carrying excess inventory.

Set your reorder points and automate replenishment

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