# Purchase planning: min/max balances and demand

URL: https://bimpsoft.com/en/help/purchasing/purchase-planning/
Updated: 2026-11-06

> Purchase planning in Bimp automatically calculates how much of a product to order. Set the demand rate, safety stock, delivery time and min/max balance in the product card, then open "Purchases → Purchase planning": the "Need to purchase" column shows the demand for the selected date.

## What purchase planning gives you

Purchase planning shows how much of each product you need to order, so you avoid shortages and do not tie up money in stock. Bimp combines the minimum balance, reserves for customer orders, sales rate and goods in transit into one figure in the "Need to purchase" column. The whole sequence, from order to payment, is described in the [purchasing process overview](https://bimpsoft.com/en/help/purchasing/purchasing-process/).

**Example.** The company "Coffee Hub" sells coffee. For "Espresso 250 g" the demand rate is 10 pcs per day, so the report shows a larger need than for low-demand items, and the fastest-selling product is always in stock.

## How to set up the product card

You set the planning parameters in the card of each product, otherwise the calculation will be inaccurate.

1. Open **Warehouse → Products and services** and the product card.
2. In the left menu of the card, select the "Planning" section and fill in the fields:
   - "Demand rate per day": the average number of sales per day; if you leave 0, Bimp calculates it from the sales of the previous month;
   - "Safety stock, days": a buffer in case of a supplier delay or a demand spike;
   - "Delivery time, days": how many days pass from the order to the [receipt of goods](https://bimpsoft.com/en/help/purchasing/goods-receipt/).

   ![The "Planning" section of the product card: "Demand rate per day" is 1, "Safety stock, days" is 5, "Delivery time, days" is 3; on the right are the cards "Availability", "Supply", "Cost"](https://bimpsoft.com/help/_img/1c62325f-0d0d-4d94-9ac4-3d080596d58f.webp)

3. Go to the "Accounting" section and fill in "Min balance" (the threshold below which stock should not fall) and "Max balance" (the level of full replenishment).

   ![The "Accounting" section of the product card: "Min balance" is 50, "Max balance" is 500, plus the fields "Supplier", "Retail category", "VAT"](https://bimpsoft.com/help/_img/f9a8f53d-bd28-41aa-b280-db7921306a6f.webp)

> [!TIP] The minimum and maximum balance are the basis of the formula. Without them, the need is calculated only from demand and reserves.

## How to generate the purchase demand

The planning report opens in the **Purchases** section, on the "Purchase planning" tab. For each product it shows the supplier, current balance, reserves, available balance, the needs from customer orders and production orders, and the "Need to purchase" column.

![The "Purchase planning" tab: the "Plan until" field, the "Need to purchase" switch, a table with the columns "Product", "Supplier", "Need to purchase", "Current balance", "Reserve", "Available balance"; the "Total" row at the bottom](https://bimpsoft.com/help/_img/dc373ae4-9007-4d72-abde-bf5d5822a1b2.webp)

The calculation formula:

**Need to purchase = Min balance + Reserves + (Demand rate × Planning depth) − Physical balance − Expected deliveries**

| Component | What it means |
|---|---|
| Reserves | goods reserved for customer orders, work orders and production orders |
| Physical balance | free balance in the warehouse (balance minus [reserve](https://bimpsoft.com/en/help/sales/reserves/)) |
| Expected deliveries | goods in transit from the supplier under orders already created |
| Planning depth | the number of days from today to the "Plan until" date |

**Example.** Min balance is 50 pcs, there are no reserves, demand rate is 1 pc per day, depth is 31 days, balance is 0, no deliveries in transit. The need: 50 + 0 + 1 × 31 − 0 − 0 = 81 pcs.

By default, Bimp plans for 31 days. To change the horizon, select a date in the "Plan until" field and the need is recalculated. A shorter horizon reduces the need for fast-selling products. Increasing the safety stock and delivery time increases the quantity to purchase.

## How to pass the demand to a supplier order

You pass the demand from planning to a supplier order through Excel.

1. On the "Purchase planning" tab, review the "Need to purchase" column. Use filters to limit the list by supplier, group, availability or warehouse.
2. Export the report to Excel with the Excel icon on the panel.
3. In the **Purchases** section, create a [supplier order](https://bimpsoft.com/en/help/purchasing/purchase-order/).
4. Upload the file with the **Import** button. See [Uploading items from Excel](https://bimpsoft.com/en/help/purchasing/purchase-order-import/).

> [!TIP] Filter the report by supplier to cover all missing items of that supplier with one order.

## FAQ

**How does Bimp calculate how much to purchase?**

Need to purchase = min balance + reserves + (demand rate × planning depth) − physical balance − expected deliveries. The planning depth is determined by the "Plan until" date; by default it is 31 days.

**What happens if I do not fill in the demand rate?**

If you leave 0, Bimp calculates the rate itself from the sales statistics for the previous month.

**Does planning take into account goods already ordered from the supplier?**

Yes. Expected deliveries (goods in transit from the supplier) are subtracted from the demand, so you do not order more than needed.

**How do I pass the demand from planning to a supplier order?**

Filter the products, export the report to Excel, create a supplier order and upload the file with the "Import" button.