Warehouse Picking Systems: 6 Strategies and the Tools That Support Them

By one estimate, order picking costs about 55% of total warehouse operating expenses on average. 

For successful fulfillment, you’ll need an order picking strategy that’s appropriately suited to your warehouse — and building that strategy will require some amount of experimentation, along with substantial investments in equipment. 

Six Common Warehouse Picking Strategies

When choosing a strategy, your goal isn’t to simply cut costs; you’ll also need to consider operational scale, order complexity, and efficiency. 

In this article, we’ll discuss six of the most popular warehouse picking systems and their pros and cons. We’ll also recommend products to help you maximize the benefits of each strategy.

Order Picking Strategy #1: Single Order Picking (Discrete Picking)

The most common method of order fulfillment, single order picking (or discrete picking) assigns a single picker to one customer order at a time. The picker navigates through the warehouse and collects all of the items listed on the order before proceeding to the next order.

In high-volume environments, single order picking is inefficient. Workers will move along similar routes repeatedly (in other words, inefficiently), and scaling may be difficult as order volumes increase. Still, it’s a common starting point — and for operations with less complex order profiles, the travel inefficiency might not be a significant disadvantage.

Material Handling Equipment: Pickers need basic, ergonomic equipment to support discrete picking. That means simple Flatbed Carts or Order Picking Carts, which can be custom built to match the operation’s needs. Additionally, picker-to-part systems will typically employ Gravity Flow Racks, bin shelving, or modular storage to minimize efficiency issues. 

Order Picking Strategy #2: Batch Picking (Multi-Order Picking)

In this approach, orders with similar SKUs or those located in close proximity within the warehouse are grouped into a batch. The picker then moves through the warehouse, picking all the required items for the entire batch of orders before returning to a sorting area. Within that sorting area, the collected items can be allocated to their respective orders.

Batch picking is most effective for warehouses that experience high order volumes, especially when many of these orders contain the same SKUs. It’s also beneficial for companies that typically receive orders with only a small number of SKUs. 

Material Handling Equipment: Order Picking Carts equipped with multiple compartments or totes are essential for allowing pickers to keep the items for different orders separate during the picking process. 

In more advanced implementations, wearable technology can provide pickers with route guidance and real-time updates for additional optimizations. Put-to-light systems (also called “scan and sort") can also be integrated to guide the sorting process after the batch picking is complete.

Order Picking Strategy #3: Zone Picking (Pick and Pass)

Zone picking, also referred to as pick and pass, divides the warehouse into distinct physical areas (or zones). Pickers are assigned to work exclusively within one or more specific zones.

Zone picking offers several major advantages:

• By assigning pickers to specific areas, the strategy reduces the overall travel time as workers become familiar with the SKUs within their zone. 
• That can also lead to improved picking accuracy. 
• Zone picking can help reduce aisle congestion by limiting the movement of pickers across the entire facility. 
• It allows for the specialization of picking techniques or the use of specific equipment tailored to the types of products stored in each zone.

Material Handling Equipment: Pickers typically use Order Picking Carts to move through their assigned zones and collect items. More advanced implementations may incorporate goods-to-person technologies like carousels or robotic picking systems with attached Tugger Carts within individual zones.

Order Picking Strategy #4: Wave Picking

Wave picking is a strategic approach to order fulfillment in which orders are grouped into sets (or "waves") based on various criteria such as shipping schedules, order priority, product type, or customer location. Pickers are then assigned to pick all the items required for each wave, often within defined time windows, to meet specific operational needs.

The primary advantage of wave picking is that it can synchronize the picking process with other warehouse activities, particularly packing and shipping. It’s an ideal strategy for warehouses with a large number of SKUs and high order volumes (for example, eCommerce fulfillment centers).

The implementation of wave picking heavily relies on a robust Warehouse Management System (WMS) to effectively group orders into waves, schedule picking tasks, and optimize routes for pickers.

Material Handling Equipment: Multi-tote carts are often utilized to keep items for different orders within the same wave separate. Depending on the size and nature of the items, material handling equipment like forklifts or pallet jacks may also be necessary. Many BHS Industrial Carts have fork pockets as standard features.

Order Picking Strategy #5: Cluster Picking

Cluster picking is an order picking technique that allows a single picker to gather items for multiple orders simultaneously during a single pass through the warehouse. The picker typically uses a specialized picking cart equipped with multiple totes, bins, or other containers, with each container designated for a specific order within the cluster of orders being picked. 

As the picker moves through the warehouse, they pick items for all the assigned orders in the cluster, placing each item into the correct designated container on their cart. 

Cluster picking significantly reduces travel time for pickers, as they can collect items for multiple orders in a single pass. Unlike with batch picking, cluster picking involves sorting items directly into order-specific containers as they are picked. That potentially eliminates a separate sorting step and allows for quicker shipment of orders.

Some potential disadvantages: 

• The number of orders a picker can handle simultaneously is often restricted by the size and capacity of the picking cart.
• For multi-line orders, there might be an increase in manual touches during the pack-out or sortation phase.
• If the items for the clustered orders are spread across many different zones within the warehouse, the travel time savings might not be as significant.
• Compared to discrete picking, cluster picking can be more complex. A robust WMS is essential for effective coordination. 

Material Handling Equipment: The primary piece of equipment for cluster picking is a picking cart designed to hold multiple totes or bins, allowing for the separation of items for different orders. Custom-built Order Picking Carts can significantly improve efficiency. 

Order Picking Strategy #6: Automated Warehouse Picking Systems

We could easily write several pages about the different types of automated picking systems used in modern warehouses. Some amount of automation is virtually essential for major operations, but the specific features of an automated system can vary significantly.

Some common forms of automated picking include:

• Pick-to-light systems represent a semi-automated approach that uses lights and digital displays to guide warehouse operators to the exact location and quantity of items required for an order
• Voice-directed picking offers another semi-automated, hands-free approach where workers wear headsets that provide verbal instructions on what items to pick and from which location.
• Robotic picking systems represent a more advanced level of automation, ranging from collaborative robots (cobots) that work alongside human pickers to fully autonomous mobile robots (AMRs) and Automated Storage and Retrieval Systems (AS/RS). 

Fully or semi-autonomous systems are best suited for high-volume operations, large warehouses, and businesses aiming for maximum efficiency, accuracy, and reduced long-term labor costs. 

Material Handling Equipment: Logistics trains use robotic tuggers to move carts along a set path. Quad Steer Tugger Carts (TT-QS) provide safe and efficient material handling, with enhanced maneuverability and precise tracking fidelity. Both axles steer in tandem to improve the turning radius along the entire train.

Choosing a Warehouse Picking System: Pros and Cons

Remember, what works for one warehouse won’t necessarily work for the next — even within the same industry — and the quality of your operation’s material handling equipment will play a major role in successful fulfillment. 

Another important note: In many complex warehouse operations, a single picking strategy may not be sufficient. Many warehouses adopt a hybrid approach to leverage the strengths of different strategies and address specific operational requirements.

BHS can help you build a picking system that matches the way you work. By customizing equipment to fit the task, we help operations maximize throughput, reduce inefficiencies, and find effective solutions at scale. 

To discuss material handling equipment with an expert, call 1-800-247-9500 and speak with a member of our team.