# Milk Run

**URL:** https://kaizumi.com/dictionary/milk-run

**Description:** A milk run is a fixed-route delivery system that picks up and delivers materials on a regular schedule, like traditional milk delivery.

**Category:** lean-tools

**Tags:** flow

## Definition

A milk run is a fixed-route, fixed-schedule material delivery system where a vehicle or material handler follows a predetermined route, stopping at each location to deliver materials and pick up empty containers or finished goods. Named after traditional milk delivery routes, milk runs enable frequent small deliveries rather than large infrequent batches. This supports just-in-time by reducing inventory at point of use while ensuring reliable supply. Milk runs work for external supplier deliveries and internal material movement. See a timed tugger loop traced stop by stop on a plant map in the [interactive Toyota assembly guide](/guides/toyota-assembly).

## Examples

### Manufacturing

> A supplier milk run picks up from four suppliers each morning. The truck follows a fixed route, collecting small quantities from each supplier. The factory receives four daily deliveries of smaller quantities rather than four weekly deliveries of large batches, reducing inventory and improving freshness.

### Healthcare

> An internal milk run delivers supplies to nursing units every two hours. The cart follows a fixed route, dropping off supplies and collecting empty bins for central supply replenishment. Units maintain minimal par levels because replenishment is frequent and reliable.

### Administrative

> An internal mail run follows a fixed route, collecting outgoing mail and delivering incoming items. The predictable schedule eliminates individual trips to the mail room and enables reliable delivery timing.

## Key Points

- Fixed routes and schedules enable smaller, more frequent deliveries
- Pick up empty containers and kanban while delivering full ones
- Supports just-in-time by reducing inventory at consumption point
- Works for both external supplier delivery and internal material movement

## Common Misconceptions

**Milk runs increase transportation cost.** While vehicle utilization per trip may be lower, total system cost often decreases due to reduced inventory, less expediting, and better production flow. The holistic system view matters.

**Milk runs are only for manufacturing.** Any operation with multiple pickup/delivery points benefits from route optimization and scheduled frequency—offices, hospitals, service operations.

## See Also

- [PFEP](/dictionary/pfep) - The plan that sets what each route carries, how much, and how often

Source: https://kaizumi.com/dictionary/milk-run
Licence: free to quote and cite with attribution to Kaizumi.