What is Make-to-Stock (MTS)? Definition & Manufacturing Examples

What is Make-to-Stock?

Make-to-stock (MTS) is a manufacturing strategy in which products are produced based on demand forecasts and held in finished goods inventory before customer orders are received. When a customer places an order, it is fulfilled from existing stock and shipped immediately — or within a short lead time for picking, packing, and freight. MTS is the dominant strategy for consumer goods, standard industrial components, and any product where customers expect immediate or near-immediate availability.

How Make-to-Stock Works

In an MTS environment, the planning cycle begins with a demand forecast. Historical sales data, market trends, seasonal patterns, and promotional calendars feed a demand planning process that projects how many units of each product will be needed over the planning horizon — typically 3 to 12 months.

The forecast drives the master production schedule (MPS), which specifies the quantity and timing of production for each product. The MPS feeds material requirements planning (MRP), which calculates when to order raw materials and components to support the production schedule. Production orders are released to the shop floor based on the MPS, and finished goods are received into the warehouse to replenish inventory.

The customer order decoupling point in MTS is at the finished goods level. Everything upstream — procurement, production, quality inspection — is driven by forecasts. The customer interacts only with the finished goods warehouse, experiencing short lead times (often same-day or next-day for stock items).

The fundamental trade-off in MTS is inventory investment versus service level. Carrying more inventory improves fill rates and reduces stockout risk but increases carrying costs, floor space requirements, and obsolescence risk. Carrying less inventory reduces costs but increases the chance of lost sales when demand exceeds forecasts.

Make-to-Stock Example

A manufacturer of industrial fasteners produces 3,000 SKUs. The top 500 SKUs (by annual revenue) are managed as MTS items. Monthly demand for the most popular M10 hex bolt averages 85,000 units with a standard deviation of 12,000 units. Production lot size is 50,000 units with a manufacturing lead time of 3 days and a replenishment review period of 1 week.

Safety stock is calculated at 1.65 standard deviations of demand during lead time plus review period (targeting 95 percent service level): 1.65 x 12,000 x sqrt(10/30) = 11,440 units. Reorder point is average demand during lead time plus review period plus safety stock: 85,000 x (10/30) + 11,440 = 39,773 units.

When on-hand inventory drops below 39,773, a production order for 50,000 units is released. Average inventory is approximately 50,000/2 + 11,440 = 36,440 units. At $0.08 per unit and a 25 percent annual carrying cost, this one SKU costs $729 per year to stock. Across 500 MTS items, total finished goods inventory investment is $1.8 million — the cost of offering immediate availability.

Why Make-to-Stock Matters for Production Scheduling

MTS manufacturing requires production scheduling that balances efficiency with replenishment timing. Schedulers must ensure that production orders complete before safety stock is depleted, while also minimizing changeover time by grouping similar products together. Late production in MTS does not just delay a single customer — it can empty the warehouse and cause stockouts across all customers.

Scheduling software like Resource Manager DB (RMDB) helps MTS manufacturers by scheduling replenishment orders alongside make-to-order and other priority work, ensuring that stock levels are maintained without disrupting committed customer deliveries. Finite capacity scheduling prevents the common MTS problem of releasing more production orders than the shop can handle, which leads to congestion, extended lead times, and missed replenishment targets.

Level loading — distributing production evenly across the planning period rather than producing in large surges — is a key scheduling strategy for MTS. It reduces overtime costs, equipment wear, and quality variability while maintaining consistent finished goods replenishment.

Related Terms

• Make-to-Order — The opposite strategy where production starts only after an order is received
• Master Production Schedule — The planning tool that drives MTS production quantities and timing
• Safety Stock — Buffer inventory that protects MTS service levels against demand variability

Frequently Asked Questions

Learn more in our complete manufacturing glossary or production scheduling guide.