back to glossary

Work in Progress

WIP
InventoryMFG-WIP-025

Work in Progress (WIP) is the inventory of partially finished goods waiting for completion and final inspection.

Definition

Work in Progress (WIP) refers to all materials and components that have started the manufacturing process but are not yet finished goods. This inventory category includes the cost of raw materials, direct labor, and manufacturing overhead applied to the items. WIP is a current asset on a company's balance sheet. It represents a significant investment of capital and resources.

Tracking WIP is important for understanding production efficiency. High levels of WIP often indicate problems like bottlenecks, long cycle times, or poor production scheduling. Excess WIP ties up cash, consumes valuable floor space, and increases the risk of damage or obsolescence. Lean manufacturing principles aim to minimize WIP to improve flow and reduce waste.

Manufacturers use various methods to manage and reduce WIP. A Manufacturing Execution System (MES) tracks the location and status of jobs in real time. Kanban systems use visual signals to limit the amount of WIP at any given workstation. By analyzing WIP levels, managers can identify constraints and make process improvements to increase throughput and lower inventory costs.

Formula
Ending WIP Inventory = Beginning WIP Inventory + Manufacturing Costs - Cost of Goods Manufactured
Example

A CNC machine shop starts the month with $20,000 of WIP. During the month, it adds $100,000 in material, labor, and overhead costs. It ships finished parts valued at $95,000, so the shop's ending WIP inventory is $25,000.

Frequently Asked Questions

Is having a high WIP level always a bad thing?

Not necessarily, as some WIP is needed to keep production flowing. However, excessive WIP indicates inefficiencies, ties up capital, and can hide quality problems.

How is WIP different from raw materials?

Raw materials are components that have not yet entered the production process. Once labor or machine time is applied, they become Work in Progress.

What is the main goal of reducing WIP?

The main goals are to shorten lead times, improve cash flow by freeing up capital, and expose production problems like bottlenecks more quickly.

How does a Kanban system help control WIP?

A Kanban system sets explicit limits on the amount of inventory allowed at each production stage. A new item cannot be started until a completed one moves forward, preventing overproduction.

Where does WIP appear in financial statements?

WIP is listed as a current asset on the balance sheet, typically between raw materials and finished goods.

Industry Context
Job ShopElectronicsAerospaceMetal Fabrication
INVENTORY MANAGEMENTLEAN MANUFACTURINGPRODUCTION FLOWACCOUNTINGBOTTLENECK