As one of the most important parts of an order fulfillment process, choosing the right order picking method requires careful consideration. According to research published by the Warehousing Education and Research Council, order picking consumes about 50% of a warehouse’s labor costs.
Research has shown that order picking is the number one area where businesses can improve operational efficiency and reduce costs. Yet, many companies don’t take the time to evaluate their current order-picking operations. This problem is often compounded when a business scales, as its warehousing needs can outpace existing order-picking processes.
With competition in the logistics industry becoming more fierce, choosing the right order picking strategy is critical to success. But what may be the best approach for one business might not be suitable for another. And what may be available today may not be the best choice tomorrow. To make an informed decision, businesses need to understand the different types of order-picking strategies available and analyze their current operations to determine which one best fits their needs.
What is Order Picking?
Order picking is the process of retrieving items from inventory to fulfill customer orders. It’s the first step in the order fulfillment process and has historically involved a warehouse worker physically locating and selecting items from shelves, bins, or racks.
Today, although not always necessary or even optimal, many businesses have turned to advanced technology to streamline order picking. Depending on factors like order volume, product size, and storage methods, businesses may benefit from utilizing one or more of the following order-picking strategies.
Discrete Order Picking
Discrete order picking is the traditional method of order fulfillment where a single warehouse worker locates and retrieves items to fulfill a single customer’s order. Otherwise known as single-order picking, this type of approach works best for businesses that have smaller order volumes.
Order A
Pick List
Fulfillment
While often not as efficient as other strategies, discrete order picking may be the best option for some businesses due to its low cost and simplicity. And because it’s a manual process, it may be more suitable for warehouses that lack the space or infrastructure to accommodate advanced automation technology.
Discrete order picking may also be the optimal choice for businesses with a wide variety of product sizes and shapes, or those that need to modify orders on the fly. Although pick rates are generally lower with discrete order picking, using this method can keep downtime to a minimum and quality control issues at bay. And while tracking order-picking accuracy and productivity may be challenging with other approaches, discrete order-picking offers greater visibility into these metrics.
Batch Order Picking
Batch order picking, one form of multi-order picking, is a strategy that groups orders together into one task to increase efficiency. Unlike discrete order picking, where a single picker retrieves items for one order at a time, batch picking involves selecting products for multiple orders simultaneously. There are several variants of this approach, including the wave-picking and zone-picking methods, each of which offers unique advantages.
Order A, B, C
Multi Order Picking
Fulfill A, B, C
In batch picking, orders are often grouped according to factors like location, order size, or customer type. Doing so can reduce the number of times a picker needs to move around a warehouse, improving overall efficiency. This method is most suitable for businesses with high order volume and a wide variety of products as it allows for more efficient movement and fewer steps per order.
Research has shown that batch picking can improve pick rates by 60% or more compared to discrete order picking, making it a popular choice for businesses that need to fulfill large quantities of orders. However, this approach requires careful inventory tracking and can be difficult to manage if a warehouse doesn’t have the right software or tools in place.
Zone Order Picking
Similar to batch picking, zone order picking is a multi-order strategy that can streamline the order picking process. In this approach, the warehouse is divided into zones, with each zone designated for a specific group of products. Also known as the “pick and pass” method, as orders come in, pickers are assigned to certain zones. Each picker only picks orders from within his or her designated zone, increasing the order-picking speed and accuracy.
Order A
Zone 1
Zone 2
Zone 3
Fulfill
Unlike batch picking, which requires the picker to take multiple trips throughout the warehouse, zone picking allows them to stay in one area and select items for multiple orders. By doing so, it reduces the number of steps per order and improves picker productivity. For warehouses with narrow aisles only suitable for single-file movement, zone picking can be especially helpful as it reduces the need for multiple pickers to pass each other.
Zone picking works best in warehouses where inventory is organized by categories or product types. It can also be a great choice for businesses with high order volume and limited storage space, as it allows for more efficient use of space. And by using a warehouse management system (WMS) that allows for order merging, each zone can be picked at the same time for even greater efficiency.
Wave Order Picking
Wave picking is another type of multi-order strategy that combines the efficiency of batch picking with the accuracy of discrete order picking. In this approach, orders are grouped together into “waves,” or batches, based on specific criteria such as priority level or customer type. As orders come in, they get added to waves sorted by the same criteria. High-priority orders, for example, may be put into one wave, while low-priority orders may be put into another.
Wave picking works best for businesses with large order volumes that need to quickly and accurately fulfill orders. This approach can increase productivity by allowing pickers to work on multiple orders in one pass, without sacrificing accuracy. Due to the complexity of the process, wave-picking operations often require warehouse management systems (WMS) for order tracking and optimization.
Additionally, wave picking may not be the best solution for businesses with a wide variety of product sizes and shapes, or for those that regularly need to modify orders. While wave picking can be a great way to increase productivity, its success is largely dependent on the accuracy of the sorting process. If orders are incorrectly sorted or merged, it can negate the efficiency gains of wave picking.
Cluster Order Picking
Cluster picking is another variation of batch picking used to fulfill multiple orders at once. Instead of picking orders and sorting them at the end of the process, like with batch picking, cluster picking requires pickers to group items together at the start. While there are several variants of cluster picking, the most common approach involves picking to a cart with multiple containers or totes. Each tote is designated for a specific order, and the picker organizes items into the appropriate tote as they go.
Vertical lift modules (VLMs) are often used in conjunction with cluster picking to hold the totes and optimize storage space. This approach is ideal for businesses that deal with a high volume of orders with a wide variety of products. Additionally, because all items are sorted as they’re picked, there’s no need for additional sorting or merging at the end of the process.
Given the complexity of the system, cluster picking is best suited for businesses with warehouses that are already well-organized and have software to track orders. Without the right tools in place, managing a cluster-picking operation can be difficult and often leads to errors. Even with a warehouse management system, it’s not uncommon for pickers to put items in the wrong tote, resulting in a longer order-fulfillment time.
Assessing Your Business’s Needs
Choosing the right order-picking strategy for your business can be a challenge if the factors influencing picking performance aren’t considered. Before deciding on an approach, it’s important to assess the size and complexity of your operations. Order volumes and the layout of your warehouse will play an important role in determining which order-picking strategy is most suitable for your business.
Are your orders large or small? Are they single-item or multi-item orders? Different order-picking methods work better for different types of orders and operations. For instance, discrete order picking might be ideal for businesses with smaller order volumes, while batch or zone picking are are more efficient for larger order quantities.
Identifying any unique challenges or constraints your business faces is also crucial. Are there specific product characteristics that require special handling? Do you have limited space or resources? Does your warehouse have aisles that are too narrow for multiple pickers to pass each other? Taking into account such factors can help optimize your order-picking process and maximize efficiency.
It’s also important to consider the types of products you’re storing and how they’re arranged. For businesses that deal with a variety of shapes and sizes, it may be best to opt for an approach like zone or cluster picking. However, if you have a smaller warehouse and the majority of your products are uniform in size and shape, batch picking may be the more efficient option.
Regardless of which strategy you choose, having the right technology in place is key for ensuring an efficient and accurate order picking process. Many of today’s warehouse management systems allow for the use of multiple order-picking approaches, as well as order merging and tracking capabilities. By investing in the right technology, businesses can save time and improve order accuracy, all while staying competitive in a rapidly evolving industry.
The Bottom Line
The right order-picking strategy can make or break a business’s operations. While there are dozens of methods and combinations to choose from, it’s important to select the approach that best fits the needs of your business. This can only be found after assessing the unique challenges and constraints of your warehouse, as well as considering the size and complexity of orders.
Method | Cost | Complexity | Throughput | Ideal For |
|---|---|---|---|---|
Discrete | Low | Very low | Low | Low order volumes, bulky products |
Batch | Mid | Mid | High | High order volume, similar SKUs |
Zone | High | High | Very high | High volume, limited space |
Wave | High | High | High | High order volume, similar SKUs |
Cluster | High | High | Mid | High order volume, high number of SKUs |
Equally important is having the right technology to support your order-picking process. With customers demanding faster delivery times and greater accuracy, having the right tools in place can help businesses optimize their operations and stay competitive. With the right order-picking strategy and technology, and through careful planning and execution, businesses of all sizes can reap the rewards of a streamlined order-picking process.
Are you interested in learning more about how to optimize your order-picking process? Our team of warehouse management experts is here to help. Contact us today for more information or a free consultation.
