Master Production Schedule (MPS)

The Master Production Schedule (MPS) is a company's binding production master plan. It defines which products are to be manufactured in which quantities over a defined time horizon – taking into account demand, capacity, and material availability.

The MPS translates the outputs of S&OP (Sales & Operations Planning) into an actionable production plan that serves as input for MRP, procurement, and shift planning.

Position in the Planning Process

The MPS acts as the link between strategic planning and operational execution:

• S&OP plans at the product family and volume level (months, quarters)
• MPS breaks these volumes down into specific end products (weekly or daily buckets)
• MRP and detailed scheduling derive material requirements, production orders, and sequencing from the MPS

Time Fences: Balancing Stability and Flexibility

A well-designed MPS uses time-based zones with different levels of flexibility:

Frozen zone (e.g., next 1–2 weeks): The plan is locked; changes require exception approval – the plant needs scheduling stability.

Slushy zone (e.g., weeks 3–6): Changes are possible but must be coordinated with material and capacity availability.

Liquid zone (e.g., week 7 onward): High flexibility for capacity and material pre-planning.

Relevant KPIs

• Schedule adherence: How consistently is the MPS actually followed?
• On-time delivery: Actual delivery dates vs. committed dates for MPS-planned products
• Inventory levels: Overstocks vs. shortfalls for MPS items
• Capacity utilization: Does the MPS align with real capacity (OEE, bottlenecks, downtime)?

MPS in the Digital Factory

In a cloud MES architecture, a closed planning loop emerges: S&OP defines volumes, the MPS translates them into realistic production programs, the MES feeds back actual output and bottleneck data, and S&OP and MPS are continuously recalibrated. A clean interface between the ERP or APS system and the MES is a prerequisite.

FAQ

What is the difference between MPS and MRP? The MPS defines what should be produced. MRP derives from it what materials and capacities are needed. MPS is the input to MRP.

Should all items be planned in the MPS? No. The MPS focuses on end products with high value or bottleneck relevance. C-parts are managed through MRP or simpler replenishment methods.

How often is the MPS updated? Typically weekly on a rolling horizon – with the principle that the frozen zone should not be changed without good reason.