The four components
Total lead time is rarely one number. Order processing (supplier confirms and queues), production (manufacturing or picking), transit (freight or last mile) and buffer (customs, weather, holidays). Adding them explicitly stops the classic mistake of using the supplier's quoted production time as if it were door-to-door.
Why buffer is not padding
Customs inspections, port congestion and factory holidays are not hypothetical — they happen every year. A 5–10 day buffer on ocean freight prevents the choice between stocking out and paying air freight, which typically costs 4–8× more.
Planning implications
- Cash conversion cycle = lead time + DIO − payable days
- A 50-day lead time means ordering before you know this month's sell-through
- Two suppliers can halve effective lead time at a small unit-cost premium
- For Q4, add two weeks to every estimate and order earlier than feels necessary
Use it with the reorder point
Feed the total into the reorder point calculator, and re-check it each quarter — lead times drift, especially across peak season.
Frequently Asked Questions
What is a typical lead time from China to the US?
30–45 days door-to-door by ocean plus production time; air freight is days but far more expensive.
Should buffer be included in planned lead time?
Yes — planning without it means your plan assumes everything goes right.
Does lead time include customs?
It should; clearance can add 1–10 days depending on broker and inspection.
Assumptions & disclaimer
Results are estimates for planning. Fee schedules, tax brackets and deduction limits change; confirm current figures with the marketplace, the IRS or a qualified accountant before making decisions. Nothing here is financial, tax or legal advice.
Privacy & Your Data
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