Importing from China: how to plan stock around long lead times
By Andrew Simpson, founder of Canopy Inventory. Last updated .
Quick answer
With long lead times, plan around two numbers: your full lead time (from placing the order to having stock you can sell) and the target cover you want to hold after the delivery lands. Reorder when the stock you have, plus stock already on order, will not last beyond your lead time plus safety stock. Order enough to cover lead time + target cover + safety stock days at your daily sales rate, minus the stock you have and the stock already on order.
Measure the full lead time, not the shipping time
For an overseas supplier, lead time is every step between placing the order and having stock you can sell: confirming the order and paying the deposit, production, getting the goods to the port, sea or air freight, customs clearance, delivery to your warehouse, and receiving and putting the stock away.
Use your own history rather than the supplier's quote: for your last few orders, count the days from order date to the date the stock went on sale. If those vary a lot, use the longer end, or hold more safety stock. Our lead time guide covers the calculation step by step.
Long lead time formulas
- Lead time (days) = order confirmed and paid + production + to port + freight + customs + delivery + receiving
- Stockout date = the day stock runs out at your daily sales rate, counting deliveries already on order on their expected dates
- Reorder-by date = stockout date − (lead time days + safety stock days)
- Order quantity = (lead time + target cover + safety stock days) × daily sales rate − (available stock + units on order)
- Then round up to the supplier's carton or pack size, and raise to the minimum order quantity if it is lower.
Worked example: a 100-day lead time
Example (round made-up numbers). A product sells 10 units a day. The lead time is 100 days: 45 days of production, 40 days of freight and 15 days for customs, delivery and receiving. You hold 14 days of safety stock and want 60 days of target cover after each delivery. You have 900 units available and a purchase order for 500 units due in 60 days.
Stockout date: on day 60 you have 900 − 600 = 300 units left, plus the 500 arriving, so 800 units. They last another 80 days, so stock runs out on day 140.
Reorder-by date: 140 − (100 + 14) = day 26. You have 26 days to place the next order.
Order quantity: (100 + 60 + 14) × 10 = 1,740 units needed, minus 900 available and 500 on order = 340 units. With cartons of 50, round up to 350. If the supplier's minimum is 500, the order becomes 500, and the extra 150 units are about two more weeks of cover.
Notice that with a 100-day lead time you will often have two or more orders open at once. Keeping a list of them, with expected dates, is what stops you double-ordering or missing a gap.
Practical tips for long lead times
- Record the real lead time of every order, so your planning uses your supplier's actual performance.
- Ask for supplier holiday dates early. Many factories close for Chinese New Year, so orders placed just before it can take far longer than usual.
- Watch minimum order quantities on slow sellers. A minimum that is many months of cover is a cash decision, and can become dead stock.
- Use air freight for urgent top-ups only. It is faster and usually costs more per unit, so it suits a best seller about to run out.
- Plan seasonal products further ahead. See Christmas stock planning for the by-hand method.
How to track stock on order in Shopify
- Create a purchase order in the Shopify admin. Shopify describes a purchase order as listing the products, quantities, costs, payment terms and supplier details for an order.
- Mark the purchase order as Ordered once the supplier confirms it.
- Create an inventory transfer for the purchase order to track the shipment, receive the stock (in full or in part) and add cost adjustments.
- Until it is received, stock on its way shows as incoming and cannot be sold. Once received at the location it becomes available.
- Keep the expected arrival date for each order in your own plan, so you can check it arrives before your stockout date.
How Canopy Inventory does it
Canopy Inventory, a read-only Shopify app coming soon to the Shopify App Store, works out weeks of cover from Shopify's available stock; incoming stock is not included in weeks of cover. On the Growth and Pro plans you enter incoming purchase orders by hand (Canopy does not read Shopify's purchase orders). Units on open orders are deducted from the suggested buy quantity, and dated order lines are added on their expected date when working out the stockout date.
Lead time can be set from 0 to 365 days. The fresh-install default is 30 days, so importers should change it: shop-wide on the Free plan, or per supplier and per SKU on Growth and Pro. While a SKU is still on the default lead time, its confidence badge shows Medium at best. The suggested buy quantity covers lead time, target cover and safety stock days, rounded up to your pack size and then raised to your minimum order if lower. Cash to buy uses your Shopify cost per item, so it is the product cost only. See how Canopy calculates.
Plan reorders around long lead times for every SKU
Canopy Inventory shows how many weeks of stock each SKU has left, when it runs out and what to reorder. Read-only. Free for your 50 most recently sold SKUs.
Sources
- Shopify Help Center, purchase orders: help.shopify.com/en/manual/inventory-and-locations/purchase-orders
- Shopify Help Center, inventory transfers: help.shopify.com/en/manual/inventory-and-locations/inventory-transfers
- Shopify Help Center, inventory states (available, committed, unavailable, on hand, incoming): help.shopify.com/en/manual/products/inventory/managing-inventory-quantities/inventory-states
- How Canopy Inventory calculates each figure: How Canopy calculates
Last updated 6th November 2026: rewritten around planning for long lead times, with a worked example and Shopify purchase order steps. Unsourced figures and timings removed.
Frequently Asked Questions
It depends on the supplier, the product, the time of year and the freight method. Measure your own: for your last few orders, count the days from placing the order to having the stock on sale, and plan with the longer end.
Enough to last until the next delivery plus a safety buffer. In practice, reorder when stock and stock on order will not last beyond your lead time plus safety stock days, and order enough for lead time + target cover + safety stock days.
Mark the purchase order as Ordered, create an inventory transfer for it, and receive the stock on the transfer when it arrives. Until then it shows as incoming, and once received it becomes available.
Ask each supplier for their closure dates well in advance and place orders early enough that production finishes before the break, or hold extra cover to see you through it.
No. On the Growth and Pro plans you enter incoming purchase orders by hand, and Canopy deducts them from the suggested buy quantity and counts dated lines in the stockout date.
Related pages
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