Order Picking: Meaning, Methods & Best Choice for Your Grocery

In e-grocery, every second counts. A customer’s trust can be won - or lost - in the time it takes to prepare an order.

Behind the scenes, order picking is where most operations succeed or fail. It drives up to 55% of fulfillment costs, and even small inefficiencies cascade into delays, substitutions, and disappointed shoppers.

Grocers who optimize picking don’t just save money; they deliver faster, fresher, and more reliable orders, turning fulfillment into a competitive advantage.

This article explores the main picking methods, the problems that hold operations back, and how smarter tools built for grocery can make the difference.

TL;DR

What is order picking, and why is it essential in e-grocery?

At its simplest, order picking is the act of preparing items for customer orders. But in e-grocery, the stakes are higher: picking defines how fast, accurate, and profitable your operations can be.

Rather than being a back-end detail, it’s the single most impactful step in fulfillment, and the one most vulnerable to inefficiency.

Understanding the primary order picking methods

To evaluate if your current or future platform supports smart fulfillment, you must first understand the major picking strategies and where each fits in.

Batch picking

Pickers handle multiple orders simultaneously, grouping items together to minimize travel time. It’s especially effective when several orders contain similar products: milk, bread, eggs. Instead of walking the same aisle ten times, a picker does it once. This reduces labor and speeds up fulfillment. Batch picking demands a backend system to efficiently group orders and guide pickers to prevent errors or cross-contamination between orders.

Zone picking

The store or warehouse is divided into zones. Each picker is responsible for one zone, and orders are assembled as they move through zones. This method works well in extensive facilities and helps eliminate redundant travel. Once pickers in each zone gather their items, the orders are consolidated. Zone picking scales well but requires a coordinated workflow and technology support to manage order merging.

Wave picking

Wave picking organizes order picking into scheduled waves, often aligned with delivery time slots, shipping cutoffs, or geographic areas. It helps balance workloads and ensures that orders go out on time. This approach demands high planning and real-time visibility into order status, picker availability, and logistics windows.

Technology-assisted methods

Modern picking is increasingly supported by technology like Pick-to-Light systems (which use lights to indicate product locations), voice-picking systems (hands-free audio guidance), or mobile scanning apps. These systems reduce human error, speed up picking, and minimize training time.

💡 Industry Insight: Many grocers are now experimenting with waveless picking, where orders are continuously released in real time instead of scheduled waves. This reduces idle time and makes fulfillment more responsive.

The real problems behind inefficient picking operations

Even with the right picking strategy, many grocery e-commerce businesses run into persistent fulfillment problems, most of which stem from platform limitations or poor integration.

1. Inventory inaccuracy

When products aren’t where the system says they are, pickers waste time looking or skip the item entirely. These issues multiply quickly without live inventory tracking tied to your storefront and warehouse.

2. Human error

Manual picking or paper-based systems lead to frequent mistakes. Missed items, wrong quantities, or incorrect brands damage your reliability. A modern WMS with barcode scanning and mobile apps is essential to close this gap.

3. Lack of prioritization

Some orders are time-sensitive (like express deliveries), but many systems process orders in the order received. Without prioritization rules based on urgency or perishability, you risk missing key delivery windows.

4. Labor dependency

Rising wages and staff shortages make labor-heavy processes difficult to sustain. This is why automation and cloud-connected tools, including AGVs (Automated Guided Vehicles) and wearable scanners, are becoming more common in grocery fulfillment.

5. Communication breakdowns with customers

When items are out of stock, many platforms offer no way for pickers to suggest replacements or contact the customer mid-pick. This leads to partial shipments, abandoned orders, and frustrated customers.

These issues aren’t solved by “hiring smarter” or “working faster”; they require a platform built for the e-grocery operational needs. This is where Wave Grocery steps in.

Inventory inaccuracy, errors, labor dependency, and poor communication, are exactly what modern fulfillment technology like the Wave Grocery Picker App is built to solve. With features such as AI-driven substitutions, aisle-based mapping, real-time scanning, and instant customer messaging, the Picker App directly addresses the root causes of inefficiency.

💡 Industry Insight: Researchers are also exploring AI-driven dynamic routing using reinforcement learning to optimize picking paths in real time, reducing wasted travel.

Smarter order picking, built for grocery

Before looking at how smarter picking can solve operational challenges, it’s important to understand the scale of the opportunity. The global online grocery market is set to expand dramatically over the next decade:

Order picking is no longer just about efficiency, it’s about adapting to the rapid growth of online grocery.

• The global online grocery market is projected to grow from USD 401.8 billion in 2025 to USD 3,950.7 billion by 2035, at a CAGR of 25.1%.
• In the U.S., online grocery sales reached $9.8 billion in June 2025, with pickup channels still dominating volume.
• Analysts expect online grocery to represent nearly 17% of all grocery sales by 2029, compared to just 1.7% CAGR for traditional in‑store grocery.

These numbers make clear that grocers who fail to modernize their picking operations will face bottlenecks as demand scales.

Smarter tools, like the Wave Grocery Picker App, are designed specifically for grocery fulfillment. With features such as:

• Real-time aisle mapping
• Multi-order and batch picking workflows
• AI-driven substitution logic
• Picker performance dashboards
• Instant messaging with customers

you can reduce errors, save time, and keep pace with growing demand.

Final thoughts

At Wave Grocery, we've tackled the complexities of order picking by designing a platform specifically for grocery operations.

Unlike generic ecommerce systems awkwardly retrofitted for grocery, Wave Grocery was built from the ground up with grocery workflows in mind.

Our platform combines category-based, multi-order picking with real-time shelf-level inventory to match how stores actually operate.

Products are grouped by category and shelf location, so pickers move efficiently through the store, fulfilling multiple orders in a single pass. This reduces walking time, increases throughput, and maintains picking accuracy at scale.

When an item is out of stock, our real-time inventory system immediately offers smart substitution suggestions.

Pickers can message customers directly through the app to confirm or adjust replacements, cutting down on errors and building customer trust.

All order components -items, substitutions, customer notes, delivery windows- are consolidated in one dashboard. This shared interface improves visibility for both pickers and managers, making operations smoother and more coordinated.

If picking is slowing your team down, we've already solved the problem.

Let us show you how it works.