How to plan inventory with net 30 supplier terms

Separate payment terms from lead time

Net 30 tells you when payment is due. It says nothing about how fast the supplier can produce and ship your order. If you mix these up, you will order too late and run out of stock while waiting for goods that are still in transit.

Always set your reorder point using the supplier's real lead time, the number of days from placing the order to the stock arriving at your warehouse. Net 30 only changes when the invoice gets paid.

Use net 30 to plan cash, not stock

With net 30, you can place an order, receive the stock, and sometimes even sell some of it before payment is due. This is useful for cash flow, especially if you are ordering larger quantities to hit case pack minimums or better pricing.

Track the invoice date and due date separately from your reorder date. A simple spreadsheet column for "payment due" next to each purchase order keeps this clear, especially if you run several suppliers with different terms.

Watch for terms that change with order size or history

Some suppliers offer net 30 only after a few paid orders, or only above a minimum order value. If a supplier starts you on prepayment or net 15 and moves you to net 30 later, update your cash planning but keep your reorder point formula unchanged, since it depends on shipping speed, not credit terms.

If a supplier is slow to invoice, your net 30 clock may start later than you expect. Confirm whether "net 30" means 30 days from invoice date or from delivery date, since this affects when cash actually leaves your account.

Step by step

1. List each supplier's actual lead time in days, separate from their payment terms.
2. Set your reorder point as daily sales times (lead time plus safety days), ignoring net 30 in this calculation.
3. Record the invoice date and net 30 due date for every purchase order as it is placed.
4. Build a simple payment calendar so you know what is due each week, independent of your reorder schedule.
5. Reorder based on stock levels and lead time, not based on when the last invoice is due.
6. Review supplier terms periodically, since minimums or history may unlock better terms over time.

Worked example

Say your supplier has a 14-day lead time and offers net 30 terms. You sell 6 units a day of a product and keep 5 days of safety stock. Your reorder point is 6 x (14 + 5) = 114 units on hand. You place the order when stock hits 114, the invoice is dated the same day, and payment is due 30 days later, well after the stock has already arrived and started selling. The net 30 term gives you roughly two extra weeks of cash runway after the stock lands, but it did not change when you needed to place the order.

How SteadyShelf helps

SteadyShelf calculates order-by dates from each supplier's lead time and safety days, which keeps your reorder timing correct regardless of payment terms. It does not track invoices, payment due dates, or accounting, so you will need to manage net 30 schedules and cash flow separately, for example in a spreadsheet or your accounting software.

$29/month flat, unlimited products and suppliers, 30-day free trial. Run the numbers now with the free reorder point calculator.

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• How to plan safety stock for your top sellers
• How to plan size curves for apparel
• How to prevent overselling
• How to plan inventory when your supplier closes for Chinese New Year

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