Inventory how-to

How to order to case packs without overbuying

Order the nearest case pack multiple that still covers your real need, and let your cover days absorb the rounding, not your gut.

Short answer: Order the nearest case pack multiple that still covers your real need, and let your cover days absorb the rounding, not your gut. If a case pack is bigger than what you need, shorten the order cycle or lower safety days slightly so you are not sitting on excess for months.

Why case packs cause overbuying

Case packs force you to round up. If your calculated need is 14 units and the case pack is 12, you either order 12 (short by 2) or 24 (long by 10). Most stores default to rounding up every time, which quietly inflates stock across every SKU, every order.

Calculate the real need first, then round

Work out daily sales, lead time, and days of cover before you think about case packs. Get a clean number first. Only after that do you round to the nearest case pack, and round to the closest multiple, not always up.

Use cover days to offset the rounding

If a case pack forces you to take more than you need, shorten your next order cycle or reduce safety days for that SKU so the surplus gets sold down before you reorder again. If a case pack consistently gives you months of extra cover, ask the supplier about a smaller minimum.

Watch slow movers and large case packs together

The combination that overbuys you most is a slow-selling SKU with a large case pack. A case of 50 on an item that sells 1 a day is 50 days of stock minimum, every time you reorder. For these, consider whether the SKU is worth carrying at that minimum, or find a supplier with smaller packs.

Step by step

  1. Calculate daily sales and raw order quantity before applying any rounding.
  2. Round to the nearest case pack multiple, not automatically up.
  3. If rounding up adds more than a few days of extra stock, shorten the next order cycle to burn it off.
  4. For slow movers, check how many days of stock one case pack represents before ordering.
  5. If a case pack regularly leaves you overstocked, ask the supplier for a smaller minimum or pack size.
  6. Review case pack sizes against sales speed every few months, since sales pace changes.

Worked example

Say a SKU sells 2 units a day, lead time is 10 days, and you want 14 days of cover. Raw need: 2 x (10+14) minus nothing on hand = 48 units. The supplier's case pack is 20. Two cases give 40 (short of plan), three cases give 60 (12 units over). Taking three cases means those extra 12 units are 6 days of stock beyond plan, so you shorten the next order cycle by about 6 days to compensate instead of carrying it forward indefinitely.

How SteadyShelf helps

SteadyShelf rounds suggested order quantities to each supplier's case pack and minimum automatically, so you do not do this math by hand per SKU. It does not decide whether to round up or down for you beyond nearest valid pack, so for slow movers with large case packs you still need to judge whether to carry that SKU at all.

$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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FAQ

What if the case pack is much bigger than my normal order size

Order less often but in full cases, and extend your days of cover assumption to match. If a case of 100 covers 2 months of sales, treat your reorder point as roughly 2 months out instead of trying to order small amounts more frequently.

Should I always round down instead of up to avoid overbuying

No. Rounding down risks a stockout before your next order lands, especially with long lead times. Round to whichever case pack multiple is closer to your calculated need, and use safety days to cover the gap if you round down.

Let SteadyShelf do this math for every SKU

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