Can Your China Supplier Meet the Delivery Date? Check the Production Slot

A supplier may quote a high monthly output and still lack a workable slot for your order. Before you commit, test the schedule for the specific product, line, and delivery window: how many good units can the factory finish after downtime and current commitments, and what evidence will show that production is on track?

A quoted line rate is not an available slot

Ask which machine or production line will make your product, which operations it must complete, and how many hours are actually scheduled for it during your requested window. A catalogue rate or best-shift result is only a starting point. It does not account for changeovers, maintenance, staffing, product-specific cycle times, or units that fail inspection.

Request the assumptions behind the supplier’s number: planned run hours, demonstrated output for the same or a comparable product, expected first-pass yield, and any known downtime. Check the bottleneck too. A fast assembly line cannot compensate for a slower molding, finishing, testing, or packing step if that step determines when finished goods are ready.

Keep the stages distinct: units started, units completed, units passed, and units packed are not interchangeable. Ask the supplier to state which measure supports the promised date. Record the product version and line being discussed; a rate from a different model or process may not apply.

Subtract existing orders and outside work

Capacity is a time-bound allocation, not a factory-wide headline. Ask for the production week or weeks proposed for your order, the shifts assigned, and the other work already scheduled on the same bottleneck equipment. A redacted weekly loading plan can show hours committed without exposing other customers’ names or prices. Compare the remaining hours with the hours your order needs, including setup and any product-specific changeover.

Ask who will perform each critical operation. If the supplier plans to subcontract painting, sewing, assembly, or another step, request the subcontractor’s identity and location, the planned dates, the quantity assigned, and who checks the output. Confirm that the main supplier remains responsible for meeting your specification and agreed schedule. A subcontracted step can introduce a second queue, transport time, and another handoff; if it is not included in the plan, the capacity estimate is incomplete.

Do not treat confidentiality as a reason to demand competitors’ commercial details. Ask instead for customer names and prices to be masked while the relevant line load, dates, and allocated hours remain visible.

Ask for evidence at buyer-controlled milestones

Use evidence tied to events you can verify, not a single reassuring promise. Before production, check that the approved specification, materials, tooling, and line allocation match the order. During production, agree on a dated update showing quantities started and completed against the plan. Before shipment, reconcile accepted quantity and packing status with the purchase order and inspection results.

Name the person who will send each update, its due date, and what happens if a checkpoint is missed. A dated production record or live walkthrough of the relevant process can help you test a claim; one photo of a busy factory does not establish that your order has a reserved slot. If the supplier reports a delay, request the revised quantity-by-date plan and identify whether the cause is labor, materials, machine time, rework, or subcontracting.

Put the agreed product version, quantity, milestones, reporting method, and permitted schedule changes in the purchase documents. Agree in advance how you will handle a missed milestone, a proposed substitute line, or an undisclosed subcontractor. A sample proves what was approved, not that the factory has time to reproduce it at scale.

Use this pre-order capacity checklist

1. Identify the product version, critical processes, bottleneck equipment, and proposed factory location.
2. Request scheduled run hours, product-relevant output data, downtime assumptions, and expected first-pass yield for the delivery window.
3. Review a redacted line-loading plan and subtract existing commitments from the same equipment and labor pool.
4. List every subcontracted step, its planned dates and quantity, and the party responsible for quality and schedule.
5. Set dated evidence checkpoints for material readiness, production start, progress, accepted units, and packing.
6. Record who reports progress and the agreed response to a missed date or changed production route.

If the supplier cannot answer a key item, label that capacity as unverified rather than silently treating it as available. Recheck assumptions when the specification, quantity, or delivery window changes.

Hypothetical example: a line that looks available

Suppose a supplier proposes one line for 8 hours a day over 20 days: 160 scheduled hours. The line’s quoted rate is 50 units an hour, but the plan sets aside 40 hours for changeovers and maintenance. That leaves 120 productive hours, or 6,000 gross units. At an assumed 95% first-pass yield, the plan gives 5,700 good units. If 4,500 good units are already committed on that line, only 1,200 remain. An order for 1,500 would have a 300-unit shortfall unless the supplier identifies and supports additional capacity.

These figures are illustrative, not a factory benchmark. Ask the supplier to validate each assumption with product-relevant records. If extra shifts are proposed, confirm the actual dates, line, staffing, and cost, then reassess the schedule. Where that changes the quote, compare it on a consistent basis with a landed-cost review. If a custom tool is on the critical path, confirm its readiness and acceptance plan; see this guide to tooling ownership and transfer.

Frequently asked questions

What if the supplier will not share other customers’ orders?

Ask for an anonymized line-loading view that shows dates, hours, and committed quantities without customer identities or pricing. If the supplier cannot share even that, ask for a live walkthrough of the relevant schedule or a smaller initial commitment with an agreed progress checkpoint before scaling up.

What if the supplier says capacity depends on final artwork or a design approval?

Treat the slot as conditional. Record which inputs are still open, who must approve them, and the date by which the factory will revalidate machine time after approval. Do not count a provisional slot as confirmed capacity until the supplier confirms the revised schedule in writing.

What if the promised quantity works only with overtime?

Request a revised plan showing the overtime dates, which line and process will run, the expected output, and the added cost. Decide whether to accept that plan or split the delivery; if you choose a split, document the quantity and acceptance point for each shipment before production begins.