Inventory how-to

How to plan inventory for domestic suppliers

Domestic suppliers usually mean short lead times, so you can run leaner stock and smaller safety buffers.

Short answer: Domestic suppliers usually mean short lead times, so you can run leaner stock and smaller safety buffers. Plan around your actual lead time plus a small cushion for delays, then set reorder points per SKU so you order before you run out.

Why domestic suppliers change the math

Short lead times mean you do not need to hold weeks of safety stock. A supplier that ships in 3 to 5 days lets you reorder often, in smaller batches, and keep less cash tied up in inventory. The main risk is not lead time length, it is lead time variability: a domestic courier delay of even 2 to 3 days can matter more proportionally than the same delay on a 60-day overseas shipment.

Set a realistic lead time and safety days

Track actual order-to-receipt time for each domestic supplier over your last several purchase orders, not the time they quote you. Add safety days based on how consistent they are. A supplier who ships reliably in 4 days might get 2 safety days. A supplier who sometimes takes 4 days and sometimes takes 10 needs more, even if they are local.

Order smaller and more often

With short lead times, you can afford to order in smaller quantities more frequently instead of stockpiling. This keeps inventory fresher, reduces cash tied up in stock, and lowers the cost of a forecast being wrong, since you will reorder again soon anyway. Watch supplier minimums and case pack sizes, since these can push you to order more than you need.

Watch for minimums that undo the benefit

Some domestic suppliers still require a minimum order quantity or case pack size. If that minimum covers 10 weeks of sales for a slow mover, your short lead time advantage disappears for that SKU. Flag these SKUs separately and consider ordering them less often, in full minimum batches, while fast movers get reordered weekly.

Step by step

  1. List each domestic supplier and their real average lead time from your last 5 to 10 orders.
  2. Set safety days per supplier based on how much that lead time varies, not a flat number for all suppliers.
  3. Calculate reorder point per SKU as daily sales times (lead time plus safety days).
  4. Check each SKU's order quantity against the supplier's case pack and minimum order size.
  5. Reorder on a tighter cycle, weekly or twice weekly, for your fastest-moving SKUs with short lead times.
  6. Review and update lead times every few months, since domestic shipping times drift too.

Worked example

Suppose you sell a kitchen gadget averaging 6 units a day, sourced from a domestic supplier with a 4-day lead time and 2 safety days. Your reorder point is 6 x (4 + 2) = 36 units. You currently have 50 units on hand and nothing on order, and you want 10 days of cover after the order arrives. Order quantity = 6 x (4 + 10) - (50 + 0) = 84 - 50 = 34 units, rounded up to the supplier's case pack of 36.

How SteadyShelf helps

SteadyShelf calculates reorder points and order quantities per SKU using each supplier's lead time and safety days, and rounds to case packs and minimums automatically, which fits domestic suppliers well since their short lead times make frequent, right-sized reorders worthwhile. It does not do per-location forecasting or transfers, so if you stock domestic inventory across multiple warehouses you will need to handle that split manually.

$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

Should I use the same safety days for all my domestic suppliers?

No. Base safety days on each supplier's actual delivery consistency. A supplier with steady 3-day shipping needs fewer safety days than one with the same average but occasional 8-day delays.

Is it worth switching from an overseas supplier to a domestic one just to simplify inventory planning?

That depends on cost and margin, which is a sourcing decision outside inventory planning. From a planning view alone, domestic suppliers do let you hold less stock and reorder more often, which reduces forecast risk and cash tied up.

Let SteadyShelf do this math for every SKU

Order-by dates per supplier, seasonal forecasts and draft POs for your Shopify store. $29/month after a 30-day free trial.

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