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Commercial glossaryKeyword: lead time inventory management

Lead Time: Managing the Clock for Better Replenishment

Lead time is the total duration from placing a purchase order to the moment inventory is ready for sale.

How Shopify merchants use Lead Time

Includes production, transit, customs, and intake. Overseas fashion often takes 8–12 weeks.

Formula

Safety stock formula

Total Lead Time = Production Time + Transit Time + Customs Clearance + Receiving Time

Breaking this down allows merchants to identify supply chain bottlenecks.

What matters in practice

  • Variability is often more dangerous than long but stable lead time.
  • Should be based on historical performance, not supplier promises.
  • Seasonal peaks (Chinese New Year) can dramatically increase it.

Why it matters

Common merchant pain points

  • Ignoring customs/processing time leading to stockouts.
  • Relying on static times that don't account for global disruptions.

Native Shopify limitations

  • Shopify does not track lead times at SKU/supplier levels.
  • Manual spreadsheet entry is prone to error and rarely updated.

Benchmarks and reference points

Sea freight can add 30–60 days compared to local sourcing.

Professionals suggest adding a buffer to the 'standard' lead time.

How to apply this in practice

  1. Step 1

    Review PO History

    Look at your last 5 Purchase Orders in Shopify.

  2. Step 2

    Calculate the Delta

    Count the days between 'PO Created' and 'Inventory Adjusted' for each one.

  3. Step 3

    Average and Buffer

    Average these results and add 3-5 days of 'slop' to account for warehouse delays.

Examples

Chinese New Year

A brand adds 30 days to their standard lead time in October to account for the factory shutdowns in February.

Local Vendor Shift

To reduce cash tied up in inventory, a merchant switches to a local supplier with a 2-day lead time.

Frequently asked questions

Related resources

Related guides

Related calculators

Related glossary terms

  • Reorder Point (ROP)

    Reorder point is the inventory level at which a new purchase order should be placed so that replenishment arrives before existing stock is depleted.

  • Safety Stock

    Safety stock is the extra inventory held above expected demand to reduce the risk of stockouts caused by variability in demand or lead times.

  • Inventory Turnover

    Inventory turnover measures how many times a company sells and replaces its inventory over a given period, typically a year.